24-hour time	front
Eclipse prediction	back
Age of Moon	front
Calendar skew
Calendar type	front
Constellations (zodiac)	back
DST	front
Equinox
GMT
Leap year	front
Moon phase	front
Nodes of lunar orbit	back
Precession of the equinoxes	back
Retrograde	front
Right Ascension (Sun&Moon)	back
Rise/set (Moon)	front
Rise/set (Sun)	front
Seasons	front
Sidereal time	back
Solar time	back
Solstice
UTC
Weekday	front
Year
Zodiac	back

In addition many watches have Geneva has the following indications not usually counted as "complications":

• hour/minute/second
• am/pm
• month/day
• AD/BC (CE/BCE)

Version 3.6.3-g969858a (2011 Aug 24)

• Increase beat frequency of some watches to more closely match real-life watches
• Various minor aesthetic improvements and bug fixes

Version 3.6.1-gfbeb829 (2011 Jun 01)

• Restore missing eclipse indicator dial arc
• Various minor aesthetic improvements and other bug fixes

Version 3.6_g86b2ada (2011 Apr 28)

• First release of Emerald Chronometer HD
• Remove spurious graphics from back face
• Update minute and hour hands at the same rate as the second hands

Version 3.5-g3adc489 (2011 Mar 08)

• Fix occasional crash when re-entering from background
• Various minor aesthetic improvements and other bug fixes

Version 3.4_r6213 (2010 Dec 20)

• In-app printing of Help pages
• Make rise/set dials take precedence over hand dragging
• Various minor aesthetic improvements and other bug fixes

Version 3.3_r6175 (2010 Nov 05)

• New high-resolution artwork for Retina display on iPhone 4
• Various minor aesthetic improvements and other bug fixes

Version 3.2_r5931 (2010 Jun 11)

• Version numbers synchronized with Emerald Chronometer releases
• Slightly improve reliability of "Disable auto-lock"
• Change calendar code to be independent of OS changes to calendar database prior to 1582
• Tap location and NTP status indicators to see details
• Holding down on windows now accelerates slowly but continuously rather than suddenly going faster
• Holding down on year windows in Set mode now accelerates to a faster rate for easier access to distant years
• Help page now linked to developers' blog
• Add certain small cities whose timezone rules were not represented (e.g., Adak, Alaska and Chatham Islands, NZ)
• Various minor aesthetic improvements and other bug fixes

Version 1.0_r5081 (2009 Dec 19)

• Initial release, synchronized with version 3.0 of Emerald Chronometer.

Emerald Geneva Support

FAQ

I'm seeing crashes (Emerald Geneva just abruptly disappears).

If you see a crash with the latest versions of Emerald Geneva and iPhone OS, and you're not running a jailbroken phone (see below), PLEASE report it to the email address below.

Will it work on an iPod® touch?

Yes. But see here for more about setting your time and location correctly.

Will Emerald Geneva work without an Internet connection (eg. out in the wilderness where even cell phone service is unavailable)?

Yes. Time and location are all that we need; all of the astronomy calculations are done internally with no Internet required. See here for more about setting your time and location correctly.

The sunrise/sunset times are wrong on my iPod touch.

You may need to enter your latitude and longitude manually. You do this via the Settings panel which is accessed from the "gear" button in the lower right corner of the screen. See here for more details.

Will it work on a jailbroken iPhone?

Probably not. We don't support that configuration and we've had reports of odd problems.

What's all this about "complications"? What's so complicated about a little calculation?

Well, the calculations are actually pretty complex. But "complication" is a term of art in the horology (fancy watch) world. It refers to any watch display other than hours, minutes, and seconds (or sometimes simple day/date). See:
      http://en.wikipedia.org/wiki/Complication_(horology)
Emerald Geneva has a very large number of complications; here's a list.

I leave my iPhone in its dock to charge and love to see Geneva all of the time. But how can I do that without disabling Auto-lock completely?

There are two Settings items that let you disable Auto-lock when running Emerald Geneva, either all of the time or only when plugged in. Be careful; if the iPhone is not plugged in, leaving the display on can drain the battery in just a few hours. See here for more details.

When I start up Emerald Geneva sometimes the hands jump just as the time synchronization indicator turns green.

Yup. Until we get the first reply from an NTP server we don't really know what the right time is. It will be stable after that.

My eyes aren't what the used to be and some of those dials and hands are awfully small. Can you implement a zoom feature?

The latest iPhone and iPod touch models have a way to do a zoom on any app. Go to Settings=>General=>Accessibility and click on Zoom. The zoom gestures are explained on that page. If you don't find this setting, make sure you have the latest iPhone OS.

Since I bought Emerald Geneva, I've started getting spam about watches!

Emerald Sequoia has not ever sold, nor will we ever sell, email addresses of our customers or of anyone else who contacts us via email. We hate spam as much as you do.

It sure would be nice if ...

Don't hesitate to send us enchancement requests or ideas for new watches. Some of the ideas we've gotten have been really interesting! We're only a two-person company, so we can't promise if or when any particular request will be implemented. But the more requests we get from our customers for a particular feature the higher its priority becomes. Unless we think it's really cool and do it right away.

The iPhone isn't designed for the wrist! How can I get the full experience of actually wearing a fine mechanical timepiece?

If you're desperate, you could try this.  But we don't recommend it.

I thought upgrades were free but the App Store seems to have no option other than "Buy Now".

Yes, that's a bit odd. But it really is free. Just click the "$4.99" button and the "Buy Now" button and enter your password. After a bit you'll see a message saying, "You have already purchased this item. To download it again for free, select OK."

I tried to upgrade to the latest version and got a message saying I needed to pay again. I thought the upgrades were free?

This is most likely the result of a mix up in your iTunes configuration. It probably doesn't recognize you as the one who bought the original version, perhaps because you have more than one iTunes account.

It may also be that the account you used with the App Store app on your iPhone is not the same as the one you're using with iTunes. If so, and you don't want to change that, then just get the upgrade directly on your iPhone via the App Store application.

I want my money back <for whatever reason>

Unfortunately, Apple does not provide developers like us a way to refund or annul a purchase, as far as we've been able to discover. One thing that may work, though, is to use the iTunes® store feedback process described at
    http://support.apple.com/kb/HT1933
One of the great benefits of the way Apple set up the iPhone application distribution system is that developers don't have to get involved in the billing process. One of the negatives is that we have no direct way to help even if we want to.

Bugs

essupport@emeraldsequoia.com

Feedback

Release Notes

Emerald Geneva

Version 3.6.3

Emerald Geneva is a "Lite" version of our flagship iPhone™ app Emerald Chronometer^®.

Emerald Geneva contains only the single watch Geneva, the most complicated of the 14 watches in Emerald Chronometer, and does not have (or need) the mechanisms to switch between watches; but it is otherwise identical to Emerald Chronometer's version of Geneva. All of the supporting technology, including NTP (atomic time), the highly accurate astronomical data from 4000 BCE to 2800 CE, and the ability to select locations and time zones in a variety of ways, carry over from Emerald Chronometer unchanged.

Thus to learn about Emerald Geneva, you can read about:

• The specific hands and dials on the watch Geneva
• General Emerald Chronometer features, keeping in mind that watches other than Geneva are not included in this app.

Customer Support

Copyright © 2010 Emerald Sequoia LLC, all rights reserved.

Astronomical algorithms and data tables derived from Lunar Tables and Programs from 4000 B.C. to A.D. 8000, by Michelle Chapront-Touzé & Jean Chapront, copyright 1991, and Planetary Programs and Tables from -4000 to +2800, by Pierre Bretagnon & Jean-Louis Simon, copyright 1986, both published by Willmann-Bell, Inc. Used with permission of the copyright holder.

NTP code derived from public domain sources covered by these copyrights.

NASA images of the Earth have use terms described here.

Emerald Observatory Release Notes

Version 1.3.8_g76d9b50 (2010 Sep 16)

• fix alarm set time when restarting app

Version 1.3.7_g745dc8c (2010 Sep 10)

• new NTP implementation with smaller impact on pool servers
• Earth map terminator edge now has discrete steps to match twilight markers on main 24-hour ring
• minor aesthetic tweaks

Version 1.3.6_g4e953bc (2012 Apr 12)

• delay warning when entering new time zone to give Location Services a chance to catch up

Version 1.3.5_g70d10a7 (2012 Mar 08)

• support for the Retina iPad

Version 1.3.4_gc241a34 (2011 Dec 28)

• fix alarm on autumn summer-time transition days
• different subdial tick marks for better readability
• Equation of Time hand now moves continuously instead of once per day
• Earth map daylight region border refinement

Version 1.3.3_gac932a9 (2011 Sep 10)

• fix the orientation of the Moon
• sidereal time subdial now labeled with the zodiac constellations

Version 1.3.2_g45d3ed6 (2011 Aug 10)

• require iOS 4.3
• longer Local Notification sound when Observatory is in the background
• update hands more frequently
• support Cyrillic region formats
• more precise hand drawing for alarm hand and others
• better behavior when iPad timezone changes
• minor aesthetic tweaks

Version 1.3.1_r628 (2011 Jan 18)

• resync NTP once per hour instead of once per day
• fixes for polar latitudes
• improve animation on wakeup from sleep/background
• improve twilight indicators and sun ring coloring on DST transition days
• solar midnight hand

Version 1.3_r596 (2010 Dec 07)

• eclipse simulator
• iOS 4.2 support
• alarm notification now given in iOS 4+ if app not running
• set mode buttons now have independent forward/reverse
• set mode century buttons
• fix bad anti-aliasing on small hands
• localized startup images
• minor aesthetic tweaks
• remove Gregorian calendar dial & relocate year label; textual leap year indicator

Version 1.2.5_r488 (2010 Oct 20)

• extend EOT dial to +/- 17 minutes
• transit time markers for the rise/set rings
• localized name for Chinese app store

Version 1.2.3_r478 (2010 Oct 1)

• Chinese localization
• fix bug in Japanese localization

Version 1.2.2_r452 (2010 Aug 13)

• setting the alarm time in the very near future when the NTP offset is negative now works correctly
• several other minor bug fixes
• smoother animation at startup

Version 1.2.1_r421 (2010 Jul 29)

• fix azimuth dial at the poles
• fix blinking alarm hand in Set mode with alarm OFF

Version 1.2_r408 (2010 Jul 21)

• alarm
• solar noon hand on main dial
• noon/midnight on top option
• Dutch, Italian and Spanish localization
• rotate the Moon image to match the sky
• minor aesthetic tweaks

Version 1.1_r299 (2010 May 19)

• French, German and Japanese localization
• increased contrast of the oceans in Earth view
• minor aesthetic tweaks

Version 1.0.2_r280 (2010 Apr 6)

• fix stuck second hand at startup when iPad time is ahead of NTP time
• fix crash if memory warning when flipside is up
• hide twilight hands when they're invalid
• minor aesthetic tweaks

Version 1.0.1_r264 (2010 Mar 31)

• Initial release

Emerald Observatory for iPad Support

FAQ

The alarm time gets messed up sometimes.

This is a known problem in version 1.3.7. The problem occurs when Observatory starts up and attempts to restore the alarm time from the previous session. We are working on a fix. In the meanwhile, the only workaround is to make sure Observatory is the foreground app with the correct alarm time set whenever you want to rely on the alarm.

Version 1.3.8 with a fix to this problem has been submitted to the App Store.

Will it work on an iPhone™ or iPod® touch?

No. But we're thinking about it...

Will it work on a Mac or a PC or any other smart phone?

No.

Will Emerald Observatory work without an Internet connection?

Yes. But the time may be somewhat inaccurate and you may have to set your location manually.

The alarm doesn't work if Observatory is in the background or if the screen is locked (iOS 5 or later).

Go to the Settings app, choose the Notifications item on the left side, and scroll down on the right side until you see "Observatory". Tap on it and then turn on the switch for "Sounds". That will allow the alarm sound to play even when Observatory is not active.

The alarm is difficult (or impossible) to hear.

There are several possibilities for this. You can use the "Test" button on the Info page to assist in debugging.

First, note that with the iOS 4.2 update, Apple changed the meaning of the hardware button near the volume keys; prior to 4.2, that button meant "lock orientation"; now it means "mute", as it does on the iPhone. (Though a Setting to control which meaning is assigned was added in iOS 4.3). So make sure that the switch is positioned so that the red dot is hidden.

Also note the (relatively new) control in the (separate) main Settings app, under General => Sounds, called "Ringer and Alerts" volume, and a switch ("Change with Buttons"). By default, the switch is off, which means that the hardware buttons on the side of the iPad case do not control the volume of alert sounds, which is what Emerald Observatory uses to sound alarms. If Emerald Observatory's sound isn't loud enough for you, make sure that the volume slider on that panel is all the way to the right. (This new control is available in iOS 4.3.1, but I'm not sure when it appeared).

Try other "alert" sounds on the device. An easy test is to see if you can hear keyclicks when typing (but make sure that you have not disabled the keyclick sound; check the main Settings app, General -> Sounds => Keyboard Clicks).

We've also had some reports from people with their device inside a case which (partially) covers the speaker, which is near the bottom of the case near the Home button. Try with your iPad outside of the case.

My time is exactly one hour off (or 2 hours or 3).

Most likely your iPad is set to the wrong timezone. Check the Settings app, General tab, Date & Time. Even if "Set Automatically" is ON it may not be correct. Turn "Set Automatically" OFF, tap "Time Zone" and choose a city in your zone (the list of possible cities is fairly small but any city in your zone will do).

Note that even if you have the wrong timezone set the time shown in the status bar can look right since it always shows the time relative to whatever timezone is set. But for its astronomical calculations Emerald Observatory needs to know the Universal Time (UTC) and that's computed from the local time and the timezone offset.

When a Local Notification is fired for an alarm when the app is in the background, the sound keeps going even after I dismiss the dialog.

This problem occurred on iOS 4.2 but was fixed with iOS 4.2.1 and iOS 4.3. Updating your device to the latest OS should fix the problem.

The little red dot on the Earth map is in the wrong place.

Check your settings on the info page (accessed via the "i" button in the lower right corner of the screen). If "Use Location Services" is On then Emerald Observatory is getting its location from iOS. You may need to enable Location Services in the main Settings app and also make sure that the entry in that section for "Observatory" is On. If "Use Location Services" is Off then we use the value specified in the text entry boxes. Be sure to use negative numbers for west longitudes and south latitudes.

The sunrise/sunset times are wrong. The planet's azimuths and altitudes are wrong.

Check the little red dot on the Earth map at the top of the screen; it should be at your location. If not, you may need to enter your latitude and longitude manually. Tap the "info" button in the lower right corner. Or it could be your timezone; see the previous section.

The moonrise/moonset time is wrong.

Make sure you're comparing the rise/set rings to the large 24-hour numbers on the outside of the dial, not the small 12-hour numbers on the inside.

The moonrise/moonset time is wrong. It seems to be for the next day instead of today.

The way Emerald Observatory shows the rise and set times limits us to showing exactly one rise time and one set time. But there are actually 3 rise (and 3 set) times that might be of interest: the most recent moonrise, the next moonrise and the moonrise that happened on this date. Usually, the one for this date is equal to one of the others but sometimes there isn't one, i.e. the Moon doesn't rise some days (e.g. 2010 Dec 27 for Auckland, NZ). Such cases would make a mess of our display if we were to try to always show the time for this date. So what we do is show the time of the most recent rise or set event and the one after that. That is the two events closest in time to the present.

Our iPhone app Emerald Chronometer shows this information in a variety of formats. Some are just like Observatory. But some just show the rise and set times on a separate dial. In those cases, we have a little trick to display the fact that there's no rise or set at all on this date: we put both hands at the 12 oclock position and change the am/pm indictor.

All of this applies equally to the Sun and the other planets. But only in the case of the Moon does the rise/set time change rapidly enough for anyone to notice.

The colored Sun ring doesn't always match the sunrise/sunset, twilight or golden hour indicators, particularly on days with Daylight Saving (Summer Time) transitions.

Emerald Observatory shows the twilight and golden hour indicators that "go with" the associated sunrise or sunset. For example, if the sunrise for March 13 is shown, then the corresponding twilight indicators will also be for the morning of March 13. This display switches from displaying the values for March 12 to March 13 exactly at sunset on March 12 (this follows from the rule in the previous answer).

The Sun ring, in contrast, always shows the data for exactly 12 local-time hours before and 12 local-time hours after the current time. This rule is different because the Sun ring, by its nature, displays a continuously changing value for each time in the day, instead of just one or two events.

So it's possible that the Sun ring can be "out of sync" with the indicators. This is typically only visible on days with Daylight Saving (Summer) Time transitions, because only then does the sunrise time move enough to notice. But if you look closely you can see it on other days too, especially at high latitudes.

Why don't you have an option to reset the iPad's internal clock, too?

We would if we could but Apple won't let us. Generally, letting apps mess around with the system's internals is a bad idea. In this particular case, it might be OK (if Apple really trusted us) but they're certainly not going to make a special case just for Emerald Sequoia.

It looks like the planets aren't in the same positions as shown in the newspaper.

Emerald Observatory shows the heliocentric positions of the planets; i.e. from a perspective far above the Sun's north pole (though greatly out of scale!). That's often very different the geocentric position which is what is more commonly seen in newspapers etc.

Also, make sure you're not looking at the astrology section of the newspaper; their definition of the constellations doesn't match the actual present day sky.

The zodiac symbols don't match the actual positions of the constellations in the sky.

Right. They're there just as labels for the 12-hour clock. They are only very approximately related to their actual positions.

When I start up Emerald Observatory sometimes the hands jump again after the initial animation.

Yup. Until we get the first reply from an NTP server we don't really know what the right time is. It will be stable after that.

If I move forward or backward by years or by centuries, keeping the date the same, the Earth shifts in position.

That's right. From 1582 onward Emerald Observatory uses the Gregorian calendar , which keeps more or less in sync with the Earth's position (but because it does so in jumps on leap years there's a bit of a "wobble" from year to year and century to century). Prior to 1582, the Julian calendar  is used, which (because it has no leap days) does not precisely track the motion of the Earth around the Sun. Thus as you move backwards from present day to 1582, you'll see the Earth move slightly back and forth, but there will be a jump at 25 October 1582 as we shift to the Julian calendar, and then a gradual and accumulating shift every year further you go into the past (we continue to use a "proleptic" Julian calendar even prior to its historical introduction because the lack of a consistent standard prior to that time).

I can't seem to get an NTP sync.

If the NTP status indicator is flashing and the network activity indicator in the status bar is going then Emerald Observatory is trying to communicate with an NTP server. This may take up to a minute or two (though it usually takes just a couple of seconds). If after a couple of minutes the indicator is still not steady green than there's a connectivity problem. Check that you can access a reliable website (eg. google.com). If you can get to the Web but still can't get an NTP sync then the problem is likely related to a firewall issue. NTP requires that UDP port 123 be accessible. If you're using a residential DSL or cable modem you may have to adjust your firewall settings; if you're at work, you may have to call your IT department. There shouldn't really be a security issue with NTP and the amount of traffic it generates is very small.

Why is it asking to use my location?

Emerald Observatory needs to know your location in order to compute various astronomical quantities (eg. sunrise time). That's all we use it for. The data is stored on your device only. We do not transmit it anywhere. We do not sell it to anyone. We update it each time the app starts up and about once an hour thereafter. It will be copied to your computer when you sync with iTunes so you may want to encrypt your backups.

It sure would be nice if ...

Don't hesitate to send us enchancement requests. Some of the ideas we've gotten have been really interesting! We're only a two-person company, so we can't promise if or when any particular request will be implemented. But the more requests we get from our customers for a particular feature the higher its priority becomes. Unless we think it's really cool and do it right away.

Translation issues

We're English-only speakers so we have to rely on others for translation. If you find something that's poorly translated please let us know and we'll fix it up. And if you would like to help translate Emerald Observatory into another language we would greatly appreciate it. (Thanks, Ben!)

Bugs

essupport@emeraldsequoia.com

A screen dump is often very helpful. You can make one by holding down the Home button while clicking the Lock button; that puts an image of the screen in your Photos library and you can mail it from there.

We try to respond quickly but we're only a two-person company so occasional delays are inevitable.

Feedback

Release Notes

Emerald Observatory for iPad Version 1.3.7 (click for full size image)

Displays

Clock

First of all, it's an ordinary clock. The main hands (gold colored) display the hours, minutes and seconds in the usual 12-hour format. To read it more precisely use the small numbers and tick marks on the inner edge of the rings. The thin central hand with the large white arrow head and the large white numbers and tick marks indicate the time in 24-hour format (with noon on top by default).

Emerald Observatory's time may not exactly match the time in the iPad's status bar becausethe iPad's clock is often not very accurate whereas Emerald Observatory's time is synchronized with the international standard atomic clocks. This is usually accurate to about +/- 0.100 seconds. This is accomplished with the Network Time Protocol (NTP)  so it must have a Net connection to get a sync. If the Net is not available, it will fall back to the internal clock's value.

It is also possible to change the clock's time and to animate it at very high rates. See Set Mode, below.

Moon

In the upper left Emerald Observatory displays the Moon as it appears from the current location at the clock's time. When the phase is a thin crescent EO simulates the illumination of the dark side by reflected light from the Earth (this is known as "Earthlight" or "Earthshine " or "the Moon's ashen glow"). In addition, the image rotates to match the Moon's apparent orientation as it moves across the sky and changes size to match the Moon's apparent size as its distance from the Earth changes around its elliptical orbit. (EO does not show the Moon's libration.)

Animate the clock at one day per tick to see the Moon go thru its phases and size changes. Tap the phase button to see the times and dates of the quarters (New, 1st Quarter, Full, 3rd Quarter).

Earth

The map of the Earth (a NASA composite of thousands of images ) at the top of the screen shows which parts of the Earth are facing the Sun and which parts are in night. The image changes each month to reflect the changing snow and vegatation cover. The lights of mankind's cities are shown for the nighttime region. They roughly correspond to the human population density and level of energy use at the present time. (The data was collected by the US Air Force DMSP satellites in the mid 1990s.)

The small red dot on the Earth marks the current location being used by Emerald Observatory for its astronomical calculations (usually the current location but you can change it; see Settings, below). It is important that this be the location for which you want the astronomical information to be shown and that the matching timezone is set in the iPad's Settings app.

Animate at one hour per tick to see the terminator (the "edge of night") move around the world. Animate at one month per tick to see the seasonal changes; note the changing shape and position of the terminator.

Day/date

In portrait orientation the year, month, day and day of the week appear in the upper right; in landscape they're at the bottom of the screen. They are shown in the language specified in the General->International section of the Settings app. The year is shown in red for BCE dates ("Before Common Era", a.k.a. "BC"). A small indicator appears to the right of the year in leap years.

Alarm time

If the alarm is set (see Settings below) a red circle enclosing a musical symbol appears outside the main 24-hour dial to mark the alarm time. When the white 24-hour hand reaches the alarm indicator the alarm will sound.

Main dial

Rise/Set rings

There are 6 thin concentric partial rings, one for each of the classical "planets". The innermost one is for the Moon, followed by Mercury, Venus, Mars, Jupiter, and Saturn on the outside. The larger one behind the others is for the Sun. The filled region of the ring represents the time (read against the 24-hour markings) when the planet is above the horizon; it rises and sets at the ends of the arc and transits at the midpoint. Thus if the thin white arm of the 24-hour hand crosses the filled part of a planet's ring then that planet is currently above the horizon.

The large ring for the Sun is colored according to the Sun's altitude above the horizon at each time; sunrise and sunset are at the sharp boundary between red and blue.

Twilight hands

There are 12 colored hands on the 24-hour dial which mark special times related to the altitude of the Sun. The light yellow one marks the time of solar noon, when the Sun is at its highest point in the sky for the day; the dark blue one is 12 hours later when the Sun is farthest below the horizon. The orange ones mark the times of sunrise and sunset. The three blue ones mark the times when the Sun is 6, 12, and 18 degrees below the horizon which define the beginning and ending of civil, nautical and astronomical twilight . The dark yellow ones mark the time when the Sun is 15 degrees above the horizon, indicating the "golden hour" (which maybe be considerably longer than an hour at high latitudes) when the light is usually best for outdoor photography.

Note that at high latitudes when the sun's altitude changes slowly the golden and blue regions will elongate. In extreme cases some of the twilight hands will disappear altogether if the Sun never reaches their level. See this effect by changing to a high latitude on the settings page and then animating by days or months.

Timezone indicator

Between the center and the 6 o'clock position is a simple label showing the abbreviation of the current timezone. It changes to reflect daylight time (summer time) vs standard time for those timezones that observe DST. EO's astronomical calculations depend on the timezone offset and geographic location. Use the Settings app ("General->Date & Time") to change the timezone if necessary.

Orrery

Inside the main dial Emerald Observatory displays the orbital positions of the 6 innermost planets (Mercury, Venus, Earth, Mars, Jupiter, and Saturn) plus the Earth's Moon from a perspective above the Sun's north pole with respect to the present positions of constellations of the zodiac. The approximate positions of constellations are marked by their traditional astrological symbols in large gray type.

    

Note that the constellation positions shown in Emerald Observatory are based on their actual positions in the present-day sky and thus do not correspond to the definitions used by western astrologers.

The best rate for animating this display depends on which planet you're concerned with. Kepler's third law  shows that the inner planets orbit much faster than the outer ones. So animating by days works best for Mercury or the Moon whereas years is best for Saturn.

If you animate by years you'll notice that the Earth jitters a little. This is not a bug. It's because we're advancing by exactly one calendar year but the Earth's orbital period is about 365.25 days. So the Earth falls behind a little for three years and then catches up on the leap year. Prior to 15 October 1582 Emerald Observatory uses the Julian calendar  rather than the Gregorian , so you'll see the Earth jump in 1582 and then it will gradually shift in position from year to year back from that time (reflecting the error in the Julian calendar).

Inner subdials

UTC

UTC  ("Coordinated Universal Time") is a worldwide time standard based on atomic clocks that is adjusted (by the occasional addition of "leap seconds ") to be very close to the mean solar time at the Royal Observatory at Greenwich, England ("GMT"). Ordinary civil time in most locations is defined by an offset from UTC.

Solar

Solar time  (technically: "apparent solar time") is what everyone used before the invention of clocks and timezones; it will show 12 noon at exactly the time when the Sun crosses the meridian  (of course, this is also when the 24-hour hand coincides with the solar noon hand on the outer dial). Apparent solar time is what an ordinary sundial shows.

Sidereal

Sidereal time  tracks the apparent motion of the stars around the Earth; the Earth rotates exactly once in 24 sidereal hours as measured against the stars. That 24-hour sidereal day is a few minutes shorter than a solar (or civil) day because of the Earth's motion in its orbit around the Sun. A star that is overhead at a given sidereal time during the day will always be overhead at that same sidereal time, no matter what season it is.

The sidereal time dial is labeled with the abbreviations of the zodiac constellations and the corresponding numbers. The hour hand points to the constellation that is currently near the meridian.

UTC and sidereal time are shown in 24-hour format; solar time in 12-hour format.

Outer subdials

Altitude and Azimuth

The two dials on the left side of the screen show the altitude (angle of the object up from the horizon) and azimuth (angle of the object around the horizon clockwise from North) of one of the planets at the clock's time. You can cycle through the 7 "planets" (Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn) by tapping either dial.

Equation of Time

The "Equation of Time " is the difference, due primarily to the ellipticity of the Earth's orbit, between between apparent solar time (see above) and mean solar time. Mean solar time is apparent solar time averaged over a whole year. Ordinary civil time is very close to mean solar time at the standard meridian of each timezone. So EOT is the difference between your watch and a sundial on the standard meridian of your timezone.

The dial is marked in minutes; positive means the sundial is ahead. In the days of celestial navigation, the EOT for the day was an essential input to a navigator's longitude calculation.

Eclipse Simulator

The small dial labeled 'Eclipse Simulator' has three icons in the outer ring, representing the Sun, Moon, and Earth's shadow and two thin red lines indicating the nodes of the Moon's orbit (points where it intersects the plane of the ecliptic). The icons are positioned around the ring according to their geocentric ecliptic longitude. When both the Sun and Moon coincide with a node then an eclipse is possible. The area inside the ring is normally empty but near the time of a lunar or solar eclipse an animation of the eclipse will appear there. Lunar eclipses are visible from an entire hemisphere of the Earth but solar eclipses are visible only from a very small area. See here for a list of times and locations of recent and upcoming eclipses (and much more).

Since eclipses happen at (or very near) full moon and new moon, you can use the "phase" button in Set mode to move forward to new and full moon dates, and see if there is anything inside the Eclipse Simulator subdial. Eclipses will only happen when the red lines indicating the nodal points are close to the Sun and Moon. You may need to move forward or backward by hours or minutes from the phase point to see the point of maximum ecilpse at your location for a given eclipse. Note that solar eclipses, which are much rarer, typically are only visible on a portion of the Earth's surface. But you can simulate those eclipses with Emerald Observatory too, by entering the "location of maximum eclipse" into the latitude and longitude fields on the Settings page, and viewing the eclipse as it will appear there.

Emerald Observatory's database of locations for the Sun and Moon extend back to 4000 BCE, as mentioned above, but there is somewhat less precision for those early dates than there is for modern times. Since the difference between total and partial eclipse can be a small fraction of a degree, historical eclipses may not be shown with 100% fidelity. Modern events, however, are shown with very high precision.

Controls

Set Mode

Tapping the "Set" button just above the top of the main dial:

stops the clock and enters Set mode. "Set" then changes to "Reset" and two sets of buttons labeled with time units appear on either side:

The blue ones on the right move Emerald Observatory's time forward by one unit; the red ones on the left move it in reverse. The "phase" buttons change to the time of the next or previous quarter Moon (you can then read the time and date from the main display). Tapping Reset changes it back to "Set", exits Set Mode, restarts the clock, and hides the other buttons.

When the displayed time is not the current time a red label appears at the top of the screen showing the displayed time and its offset from the current time.

Emerald Observatory can be set to any date from 4000 BCE through 2800 CE.

Animation

Press and hold any of the buttons in Set Mode to animate the display (step continuously). Slide your finger off the button before raising it to "latch" the button and advance continuously. Tap it again to "unlatch" it. You can have more than one button active at once. Tap "Reset" to the return to the present time.

Hot Spots

There are two additional invisible active buttons on the screen on the altitude and azimuth dials. Tapping either of them switches both dials to display the values for the next planet in the cycle (Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn, Sun, ...). The two cycle in opposite directions to avoid the need to cycle all the way around again if you go one too far.

NTP status indicator

The dot in the lower left blinks while NTP is communicating with the servers to synchronize the time; it is steady after that process is complete. It is green if a good sync has been accomplished, yellow otherwise.

Orientation

Emerald Observatory functions identically in both orientations but its layout is slightly different when the iPad is rotated into landscape mode:

Settings

The familiar small "i" in the lower right corner flips the display to a settings and help screen:

Alarm

The first switch enables/disables the alarm. The label immediately to the right of the switch shows the alarm time even if it is currently disabled. The "Set" and "Test" buttons appear only when it is enabled. The picker wheels appear when the "Set" button is tapped; spin them to the desired time then tap anywhere outside the popup to dismiss it. Tap the "Test" button to hear the sound; tap anywhere on the screen to silence it.

The alarm will sound for about 20 seconds (10 rings) or you can tap anywhere on the screen to silence it. It is based on real time only; it does not sound if the alarm time is reached in Set mode. It will sound if the screen is locked while Emerald Observatory is running. If run under iOS 3.2 the alarm will not sound unless Emerald Observatory is the currently active app; with iOS 4.2 or later a local notification will be issued in that case.

The alarm will repeat at the same time each day.

Noon on Top

Most 24-hour clocks have midnight (0 or 24) at the top of the dial. But when the clock also shows an indication of the day/night hours it is convenient to have noon (12) on top. As there seems to be little consensus on this issue, EO lets you choose for yourself.

Use Location Services

This switch controls whether Emerald Observatory will use the iPad's builtin location finding hardware. For those situations where that is not sufficient (e.g. a WiFi-only iPad not near a registered WiFi node) you can turn the switch to OFF and enter your own values for latitude and longitude. Enter the values in decimal format with negative numbers for west longitudes and south latitudes. Check the red dot on the Earth map on the main screen to ensure the values are correct. Also make sure that the corresponding timezone is set. (The timezone abbreviation is displayed at the very top of the Settings/Help screen and on the main dial; it is set with the Settings app, "General->Date & Time".)

Disable Auto-lock

The final pair of switches disable the iPad's automatic sleep mode. The top one controls what happens when your iPad is connected to a power source, the bottom one when it's running on battery. If the switch is ON your iPad will not sleep regardless of the Auto-lock setting in the Settings app. Be careful with the 'on battery' setting; Emerald Observatory will deplete the iPad's battery in just a few hours.

Help

The remainder of the screen is a brief summary of the app's capabilities. Scroll to the bottom to see the boring copyright notices. Tap the Emerald Sequoia logo at the very bottom to get back to this web page.

Customer Support and FAQ

Release Notes

Copyright information

Emerald Time Change Log

Version 1.6.2 (2012 Sep 23)

• Support for iPhone 5
• Restore missing leading zero in seconds display

Version 1.6 (2012 Jun 02)

• High resolution images for Retina iPad
• Tentative support for leap seconds

Version 1.5 (2011 Aug 16)

• faster initial sync
• try to use local servers first

Version 1.4 (2010 Oct 13)

• additional NTP server option

Version 1.3 (2010 Jul 27)

• new cleaner graphics
• support for iPhone 4 and iOS4
• support for iPad in both orientations
• localization for most displays
• questionable "sigma" value no longer displayed in main window
• tap the offset value to redo the NTP sync (same action as tapping the lights)
• Help updated

Version 1.2.1 (2010 Apr 4)

• support portrait upside down orientation

Version 1.2 (2009 Mar 26)

• fixed server names for the UK

Version 1.1 (2008 Nov 8)

• improved network error handling

Version 1.0 (2008 Sep 4)

• initial release

Emerald Time Support

Version 1.6.2

FAQ

My iPhone™ is only off by 4 seconds; why do I need this silly app?

You don't. But some of us think such an error is insanely huge for a 21st century computer. It's just not right.

It doesn't properly work on the iPad

Please upgrade to version 1.3 or later.

The seconds have disappeared!

Tap the seconds window. That cycles between displaying the seconds with tenths, the seconds only and nothing at all. That's convenient if you find the blinking seconds annoying. But it's confusing if you don't know that. Now you do.

What does a "?" in the upper right mean?

That Emerald Time can't contact any servers. Make sure you really have internet connectivity. Be patient. Or tap the lights to force another retry. Sometimes it takes several tries.

All the servers in the list are red or gray like the picture above.

See previous answer.

What do the colors mean in the table of stats?

• Gray: no attempt has yet been made to contact this server
• Red: unable to contact the server
• Orange: making the first attempts to contact the server
• Yellow: getting data from the server but not yet enough
• Cyan: same as green but the green one had more consistent statistics
• Green: Emerald Time has suficient good data to accurately determine the server's time

What are those funny server names?

Emerald Time uses servers from the NTP Pool Project. The addresses you see are not real; they just redirect (more or less at random) to the real servers. You will not get the same real server each time. This is good.

But what if I somehow get connected to a really remote server on another continent?

It will probably work just fine. An NTP server half way around the world seems to be able to supply a more accurate time than the cell phone tower a mile away. But Emerald Time picks the best of the servers it tries anyway, so it's not likely that a really distant one will be picked.

My iPhone has GPS built in. Doesn't that have a really accurate clock?

It sure does, and it's accurate to a few nanoseconds (if it wasn't it wouldn't work). In fact, GPS receivers are very often used as the reference standard for NTP servers. But iOS does not use the GPS time information. And of course, some devices don't have GPS.

I ran Emerald Time and it got a good time setting. But when I quit the device's clock went back to what it was before.

Yeah, that's how it works. Setting the system clock requires root privileges which are granted only to Apple's own apps. This is probably a good thing in general; you really don't want random programs messing with your system.

What's that misshaped "o" at the head of the middle column?

That's the Greek letter sigma (σ) which is conventionally used to represent a standard deviation.

I'm confused about how to set "Disable Auto-Lock"...

Yes, it's a little confusing. iOS's system-wide option is called "Auto-Lock"; when it's enabled (set to something other than "Never") the screen blanks after a while. This is often not the behavior you want in an app like Emerald Time so we have an option to disable the system-wide feature for our app only. Thus when our option "Disable Auto-Lock" is ON the screen should not blank out while Emerald Time is running (as if "Auto-Lock" was set to "Never"). Be careful with this when your device is not plugged in.

Bugs

essupport@emeraldsequoia.com

Feedback

Release Notes

Emerald Time

Version 1.6.2

Emerald Time is a little iPhone/iPad™ application that uses Network Time Protocol (NTP) servers on the Internet to obtain a more accurate time than is typically available from the iPhone's internal clock, which can be off by several seconds or more.

Features

Displays

The four items inside the cloud represent some of the NTP servers that have been contacted. While Emerald Time is actually in communication with a server it shows that server's time. After it disconnects only the difference between that server's clock and the iPhone's internal clock is shown. The best value (not necessarily the smallest one) is shown in green. Question marks are shown when there has not yet been a successful connection.

The red/yellow/green lights above the time show the progress of the server connections. When Emerald Time has enough good data the green light is on. The other lights appear only while data is being collected.

Controls

For the truly obsessed (and for the convenience of the developers) tapping anywhere on the cloud brings up a table of server statistics as shown to the right: "n" is the number of good/bad packets received; "offset" is the difference between that server's clock and the internal clock; "σ" is the standard deviation; "rtt" is the average round-trip time to that server (in milliseconds). The colors indicate the state of the server connection. Tap again to return to the cloud.

Tapping the offset or any of the lights makes Emerald Time immediately contact the NTP servers again to recompute a new offset. That burns up some network packets and makes a nice light show, especially with the server info table showing.

The "i" brings up the built-in version of this documentation.

Notes

Emerald Time has an option to disable the global Auto-lock so that the device does not sleep while Emerald Time is running. You set this option in the applications section (at the bottom) of the Settings app. This will drain your battery in just a few hours; best to keep it on the charger.

Emerald Time's Settings app section also has a provision for adding an additional NTP server. You may enter either a hostname an IP address. Restart the app or tap the lights to do a new sync after changing the option.

Emerald Time periodically goes out to the Internet to get data from the NTP servers so beware of data roaming charges. If the network is unavailable, it will try repeatedly with longer and longer intervals between attempts. You can always force another attempt by pressing the lights.

Emerald Time chooses which NTP servers to contact based on your locale (see Settings->General->International->Region Format). It will usually work more efficiently if you have that set correctly.

Don't be surprised if the offset changes occasionally. Devices with 3G capability frequently update their internal clocks from the cell phone network. Emerald Time sees that, contacts the NTP servers again and calculates the new offset. The displayed time should not change but the new offset may be quite different from the previous one. If your friends' devices are also running Emerald Time their offsets may be different but the displayed times should all be the same!

Emerald Time primarily uses servers from the NTP Pool Project but it also includes Apple's default NTP server(s).

Emerald Time Support and FAQ

Help Contents

Home   Chronometer

Buy Now

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Emerald Chronometer

Version 3.0

Controls

The Reset button appears whenever the watch's time is not correct. Tap Reset to return to the correct time (and exit Set mode).

With the crown out, you can tap the forward/backward button to reverse the watch's direction and to reverse the meaning of the pushers and day/date window buttons. (Not present on all watches)

Tap the back button to see the other side of the watch. Many watches have additional complex displays on the back. Geneva has another complex display on the back.

Tap the night button to switch to/from night mode.

Tap the options button to show Emerald Chronometer's options settings.

Tap the info button to see the help information. Navigate like a web browser. Links marked with "" will exit Emerald Chronometer and switch to Safari. Click the Done button at the top to return to the watch display.

Tap the switcher button to enter the watch Switcher. Then just tap the name of a watch to switch directly to it. Or tap the Edit button at the top right to enter the watch Editor which lets you choose which watches appear and change their order.

Tap the grid button to enter Emerald Chronometer's 2-dimensional grid display mode where all the active watches are displayed at once. Tap a watch to return to normal view of that watch. Swipe left or right to enter the watch Editor to change which watches are displayed. The active watches will expand to fill the available space.

Indicators

You can tap the indicator lights to bring up a page that shows more detail.

Notes

Click here for an index of features and complications in all the watches.

When the watch's time is set to a value before 1 CE the year windows will be red.

When a the watch's time has been changed, its front and back will display the same time, but other watches will not be affected. time. Also, a red banner appears at the top of the screen showing the difference between the watch's display and the correct time. In grid mode, a red outline will appear around watches whose time is not correct.

Emerald Chronometer uses the iPhone's location information to calculate the times of astronomical events like sunrise and sunset. If you are unable to get a location fix or if you want to see the information for another location you can set the location manually; see Option Settings for details.

There is also an option to temporarily disable the iPhone's auto-lock feature so that Emerald Chronometer's display stays on continuously.

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Copyright © 2009, Emerald Sequoia LLC; last updated: 2011 February 17.

General rule

Similarly, the For example, the rise and set dials, which can be read to the nearest minute, are at least that accurate. But note of course that they are only valid if the rise or set point on the horizon is at exactly the same level as you are; if the Sun is setting behind a hill above you, for example, it will set much earlier than the time indicated.

The displays depend heavily on having the correct time and location. If you have NTP synchronization and Location Services turned on, the correct time zone set in the iPhone's Settings app, and have green lights at the top of the display, you can presume that everything you are looking at is as accurate as you can read it. In general, those green lights mean you have about a kilometer (half a mile) of accuracy and are within a half second of the correct time.

Specifics

Specifically, the tables employed are from Lunar Tables and Programs from 4000 B.C. to A.D. 8000, by Michelle Chapront-Touzé & Jean Chapront, copyright 1991, and Planetary Programs and Tables from -4000 to +2800, by Pierre Bretagnon & Jean-Louis Simon, copyright 1986, both published by Willmann-Bell, Inc. (the latter includes the Sun motion tables).

The algorithms presented in those books were ported to C for use in the iPhone development environment, and local caches were developed to avoid recalculation of common quantities. The time conversions in those books have been superceded by more accurate ones, described below.

As a side note, the iPhone is a potent floating-point calculating machine; every time you move the Sun or Moon hand on Mauna Kea a little bit, over a thousand double-precision sines and cosines are calculated, whose arguments are themselves each polynomial expressions with several terms, and it all gets done in much less than a tenth of a second. Early in their careers the authors of Emerald Chronometer used machines that filled whole rooms with less horsepower than the iPhone you're holding in your hand.

The RA display on Geneva displays the RA "of date", meaning the RA applied from the equniox current on the given date. This means that the Local Sidereal Time (per its definition) also displays the rotation from the equinox, and not from the equinox of J2000. It also means that the Sun, Moon, and lunar nodal points' RA "of date" may be read from that dial. The constellations are displayed in the exact orientation found in J2000, but rotated according to the precession to match their locations at the displayed time. The P03 formulae for general precession are used.

Historical data

What that means in practice is that the astronomical events happened as shown, but the time of day may not be the exact time that they happened. You can find a discussion of the various time scales involved, notably Ephemeris Time, or Terrestrial Dynamic Time, and Universal Time, in many places on the web.

And, of course, the dates of events depend on which calendar is used. Emerald Chronometer uses the Gregorian calendar for future dates and for past dates back to 1582, and the Julian calendar from 1 BCE to 1582 CE. Prior to 1 BCE Emerald Chronometer uses a proleptic Julian calendar, with leap years on 1BCE, 5BCE, etc, back every four years. Until very recently calendar representations around the world have varied widely, so using Emerald Chronometer for historical dates requires an advanced knowledge of Chronology.

Emerald Chronometer always displays UTC, and uses that as the starting point for its calculations, converting to Terrestrial Dynamic Time (TDT) using the polynomial expressions suggested by Fred Espenak at this NASA site based on the data in Morrison & Stephenson, 2004.

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Copyright © 2009, Emerald Sequoia LLC; last updated: 2009 November 25.

24-hour time	Geneva (front) Kyoto (back) Mauna Kea (front) Miami (front) Terra Vienna
Eclipse prediction	ChandraII (back) Geneva (back)
Foudroyante	Olympia (front)
Age of Moon	Geneva (front)
Alarm	Istanbul
Altitude (Moon)	Chandra (front) ChandraII (front) Haleakala (back)
Altitude (Sun)	Haleakala (front)
Altitude (planets)	Miami (back)
Azimuth (Moon)	Chandra (front) ChandraII (front) Haleakala (back)
Azimuth (Sun)	Haleakala (front)
Azimuth (planets)	Firenze (back) Miami (back)
Calendar skew	Geneva
Calendar type	Geneva (front)
Chronograph	Olympia
Compass (Sun/Moon)	Miami (back)
Compass (Sun/Moon)	Haleakala
Constellations (zodiac)	Geneva (back) Mauna Kea (front)
Countdown timer	Thebes
DST	Atlantis (front) Geneva (front) Terra (front)
Day/night	Alexandria Mauna Kea (front) Terra Vienna
Equation of Time	Mauna Kea (front)
Equinox	Alexandria (front) Geneva
Era	Atlantis (front) Chandra (back) ChandraII (back) Firenze Geneva Mauna Kea (front) Miami (back)
Flyback	Olympia
GMT	Geneva Mauna Kea Terra (front) Vienna
Jumping hand	Haleakala
Latitude	Atlantis (back)
Leap year	Atlantis (front) Geneva (front)
Longitude	Alexandria Atlantis (back)
Moon compass	Chandra (front) ChandraII (front) Haleakala (back)
Moon distance	ChandraII (back)
Moon ecliptic latitude	ChandraII (back)
Moon ecliptic longitude	Chandra (back)
Moon orientation	Chandra (front) ChandraII (front)
Moon phase	Chandra ChandraII Geneva (front) Haleakala (back) Mauna Kea (back) Terra (back)
Nodes of lunar orbit	Geneva (back)
Orrery	Firenze (front)
Power Reserve	Milano (front) Neuchatel (back)
Precession of the equinoxes	Geneva (back)
Rattrapante	Olympia
Retrograde	Geneva (front) Miami (back) Milano (front)
Right Ascension (Sun)	Mauna Kea (front)
Right Ascension (Sun&Moon)	Geneva (back)
Right Ascension (planets)	Miami (back)
Rise/set (Moon)	Geneva (front) Haleakala (back) Mauna Kea (back) Vienna
Rise/set (Sun)	Geneva (front) Haleakala (front) Kyoto (back) Mauna Kea (front) Terra (back) Vienna
Rise/set (planets)	Firenze (back) Miami
Seasons	Geneva (front)
Sidereal time	Geneva (back) Mauna Kea
Solar time	Geneva (back) Mauna Kea (back)
Solstice	Alexandria (front) Geneva
Stopwatch	Olympia
Sun compass	Haleakala (front)
Tachymeter	Olympia (front)
Timer	Thebes
Traditional japanese hours	Kyoto
Transit (planets)	Miami (back)
Twilight	Haleakala (front) Mauna Kea (front)
UTC	Geneva Mauna Kea Terra (front) Vienna
Weekday	Atlantis (front) Geneva (front) Haleakala Milano (front) Olympia (front) Terra
World time	Terra
Year	Atlantis (front) Chandra (back) ChandraII (back) Firenze Geneva Mauna Kea (front) Miami (back) Milano (back)
Zodiac	Geneva (back) Mauna Kea (front)

In addition many watches have Geneva has the following indications not usually counted as "complications":

• hour/minute/second
• am/pm
• month/day

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Copyright © 2009, Emerald Sequoia LLC; last updated: 2010 April 20.

Copyright © 2008-2011 Emerald Sequoia LLC, all rights reserved.

Astronomical algorithms and data tables derived from Lunar Tables and Programs from 4000 B.C. to A.D. 8000, by Michelle Chapront-Touzé & Jean Chapront, copyright 1991, and Planetary Programs and Tables from -4000 to +2800, by Pierre Bretagnon & Jean-Louis Simon, copyright 1986, both published by Willmann-Bell, Inc. Used with permission of the copyright holder.

NTP code derived from public domain sources covered by these copyrights.

Geocoding database derived from geonames.org.

Version 3.8-g4146bacM (2012 Jun 07)

• High-resolution images for iPad with Retina display
• Fix occasional delayed alarm on Thebes when returning from background with NTP disabled or unavailable
• Various minor aesthetic improvements and bug fixes

Version 3.7.3-g781a06e (2012 Mar 08)

• (Emerald Chronometer HD only)
• Fix crash on new iPad with Retina display
• Tweak appearance of 24-hour hand on Vienna

ECHD Version 3.7.2-g4fa2d48 (2012 Feb 10)
EC      Version 3.7.2_gb9eb6a4 (2012 Feb 06)

• Reduce footprint on devices with 256 MB RAM

Version 3.7.1-geed7cfe (2012 Feb 03)

• (Emerald Chronometer HD only)
• All of the features and fixes in version 3.7 documented below including the new full-month calendar watch Babylon
• Tell iOS not to back up generated files

Version 3.7-g05d9c82 (2012 Jan 25)

• (Emerald Chronometer only; Emerald Chronometer HD coming soon)
• New watch Babylon with full-month calendar
• Two-stage Reset button on Thebes (interval timer)
• Show Mauna Kea's and Terra's fixed moons with south up for southern observers
• Additional button on Miami back to cycle planets in opposite order
• Fix updates when running backward through midnight
• Various minor aesthetic improvements and bug fixes

Version 3.6.3-g969858a (2011 Aug 24)

• Increase beat frequency of some watches to more closely match real-life watches
• Various minor aesthetic improvements and bug fixes

Version 3.6.2-g04fe958 (2011 Jun 13)

• (Emerald Chronometer HD only)
• Warning about running EC HD under iOS 4.2.1
• Various minor aesthetic improvements and bug fixes

Version 3.6.1-gfbeb829 (2011 Jun 01)

• Allow tapping the AM/PM window in Istanbul when in SET mode to switch between AM and PM.
• Restore longer Local Notification sounds, now that iOS 4.2.1 and iOS 4.3 have restored the old OS behavior.
• Restore missing eclipse indicator dial arc
• Various minor aesthetic improvements and bug fixes

Version 3.6_g86b2ada (2011 Apr 28)

• First release of Emerald Chronometer HD
• Center the transparent "current city" indicator at the top of Terra
• Elapsed days hands on Olympia enable timing intervals up to 12 days
• Update minute and hour hands at the same rate as the second hands
• Remove spurious graphics from Geneva back face
• Various minor aesthetic improvements and bug fixes

Version 3.5-g3adc489 (2011 Mar 08)

• New hands for Haleakala and Chandra
• Fix occasional NTP crash when re-entering from background
• Various minor aesthetic improvements and other bug fixes

Version 3.4_r6213 (2010 Dec 20)

• In-app printing of Help pages
• Make Geneva rise/set dials take precedence over hand dragging
• Various minor aesthetic improvements and other bug fixes

Version 3.3_r6167 (2010 Nov 05)

• New high-resolution artwork for Retina display on iPhone 4
• Various minor aesthetic improvements and other bug fixes

Version 3.2.2_r6027 (2010 Aug 02)

• More useful azimuth displays at the poles
• Fix stuck "Loading" message after flipping front/back or day/night

Version 3.2.1_r6001 (2010 Jul 02)

• Local Notification sound now identical to normal alarm sound (increased length and volume)

Version 3.2_r5928 (2010 Jun 11)

• Local Notifications now delivered when app is not running and an alarm's time is reached
• Time base when the device is unlocked changed to avoid jumps when iPhone changes cell towers
• Slightly improve reliability of "Disable auto-lock"
• Change calendar code to be independent of OS changes to calendar database prior to 1582
• Various minor aesthetic improvements and other bug fixes

Version 3.1.1_r5693 (2010 Apr 29)

• Add certain small cities whose timezone rules were not represented (e.g., Adak, Alaska and Chatham Islands, NZ)

Version 3.1_r5659 (2010 Apr 18)

• New world-time watch: Terra
• Tap location and NTP status indicators to see details
• Holding down on windows now accelerates slowly but continuously rather than suddenly going faster
• Holding down on year windows in Set mode now accelerates to a faster rate for easier access to distant years
• UTC indicator on Vienna
• Help page now linked to developers' blog
• Fix bug where timezone failed to update at startup in auto mode
• Various minor aesthetic improvements and other bug fixes

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Copyright © 2012, Emerald Sequoia LLC; last updated: 2012 June 15.

Help Contents

Time

When all else fails, you can set the date and time and time zone manually with the Settings App: Settings -> General -> Date & Time.

Emerald Chronometer uses the Gregorian calendar for future dates and for past dates back to 1582, and the Julian calendar from 1 BCE to 1582 CE. Prior to 1 BCE Emerald Chronometer uses a proleptic Julian calendar, with leap years on 1BCE, 5BCE, etc, back every four years. Until very recently calendar representations around the world have varied widely, so using Emerald Chronometer for actual historical dates requires an advanced knowledge of Chronology (far beyond the scope of this note).

Click here for a description of the accuracy of Emerald Chronometer's astronomical calculations.

Geographic Position

Most astronomical calculations depend on your position on the Earth's surface. So Emerald Chronometer has a number of ways to for you to specify a position; they are accessed via the locations options screen:

By far the most important aspect of each of these are the switches at the top. If they're both set to "ON" then your position and timezone will be determined automatically and in most cases that will be sufficient and you can stop reading now. They are both ON by default. See below for a description of how these automatic determinations are made. When the switches are ON the rest of the screen is a read-only display. Since location and timezone are closely related the bottom section of the location screen shows the timezone that is currently in effect; it is always read-only.

Manual location setting

• Tap the search box near the top of the screen to enter the name of a city. Emerald Chronometer has a built-in list of more than 80,000 cities that it will search for your entry. Each time you type a character a new list of matches is displayed. Tap the "Search" button at the bottom of the keyboard to see the whole list. When you pick a city from that display, Emerald Chronometer will use its latitude and longitude from the internal database. The Internet is not required to use a city in the database; the map will not update without an Internet connection, but Emerald Chronometer will use the data for the city.

• When text entry field on the name entry screen is empty, a bookmark icon will appear on the right side of the field: If you tap it, the standard Address Book interface will appear. When you choose one of your Contacts, Emerald Chronometer will extract the city, state, and country information from it and display a list of cities that match. Just choose the appropriate one. (Note that Emerald Chronometer uses only the city level info; it ignores the street address. This is almost always sufficient for our astronomical calculations.)

• If you know the latitude and longitude of your location you can simply enter those values in the two text fields. The values are in decimal degrees; use negative numbers for west longitudes and south latitudes. The Internet is of course not required to enter the latitude and longitude directly; the map will not update without an Internet connection, but Emerald Chronometer will use the given coordinates.

• The small map is read-only but if you tap it a full screen map will appear. Scroll and zoom the big map using the usual iPhone map controls (flick to scroll, pinch to zoom, double tap to zoom in, double tap with two fingers to zoom out). Tap the Set button in the upper right corner of the screen to move the purple pin to the center of the crosshairs and use that location. Switch between map and satellite views with the three buttons at the top center. Return to the locations screen by tapping the Location button in the upper left.

• Finally, you can always go back to a previously used location. Just tap the Recents button and pick from the ensuing list. New entries are automatically added to the list each time you exit the location setting screen. You can remove or reorder entries in the list by tapping the Edit button.

Manual Timezone setting

If you turn the "Set Automatically" switch OFF the timezone setting screen changes to its manual entry form:

If you pick a timezone that doesn't seem to match your current location a warning box will appear. The same warning will appear if you choose a seemingly inappropriate location while the timezone is set manually. This is just a warning, Emerald Chronometer will honor your choice. But be sure you know what you're doing if you see it. Some of Emerald Chronometer's displays will be incorrect (or look very odd) if your location and timezone do not match (eg, if you're in New York City but you set your longitude to "74" instead of "-74"). If you change either one manually make sure the other one is consistent. If you allow both to be set automatically then everything is usually OK.

Auto-lock

This option applies only when Emerald Chronometer is running; it has no effect on other apps.

Auto location

Emerald Chronometer will start up assuming the same timezone and location settings as it had the last time it was run. It may then take up to a minute or so to get an accurate location fix. The location status indicator will blink during this process. If Emerald Chronometer is running when the fix is determined then the affected watch hands will move to the correct positions.

To use Location Services, you must enable it in the General section of the Settings app AND set "Use Device Location" to "ON" in the locations screen.

In order to save battery energy, Emerald Chronometer asks for its location only at startup and at 30-minute intervals. If you are in a fast-moving vehicle and want the utmost accuracy in the astronomical displays, you can force another location update by entering the location setting screen again. You can see it move in real time with the big map.

The algorithm used to determine the timezone when the "Set Automatically" switch is ON is based on the setting of the "Use Device Location" switch. If it is also ON then Emerald Chronometer just uses the timezone from iPhone OS. This is in turn based on the settings in Settings->General->Date & Time; when set to "Set Automatically" the timezone is received from the cell phone network (which is not always right). If Emerald Chronometer is in manual location mode, the auto-timezone is taken from our internal database.

Devices without GPS

SkyHook's locator

enter your own WiFi access point

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The Watches

                    

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Copyright © 2009, 2010, Emerald Sequoia LLC; last updated: 2010 April 20.

Network Time Protocol (NTP)

Every time Emerald Chronometer starts up and the "Use NTP" option is ON or whenever that option is changed to ON, the app goes out to NTP servers on the Internet and asks for the current time. It chooses a pool of servers based on the user's country setting: first from the local country's pool, then the continent pool for that country, then the global pool, and finally time.apple.com. This progression happens each time we get a new synchronization; there are four sets of servers in each pool. Emerald Chronometer compares the time thus obtained with the time supplied by the iPhone, and stores the difference as a "skew" value. This skew is applied globally throughout the application to every watch display, with a couple of exceptions described further on. display.

The size of this skew is completely dependent on how accurate the time supplied by the telephone carrier's signal is. In the SF Bay Area where the authors live, it typically varies by up to a few seconds in either direction. In other areas it is reportedly larger. The iPod touch uses a different synchronization mechanism, synchronizing with your desktop computer, so there it will depend on the accuracy of your desktop computer. (You can see the current skew value by tapping on the upper lift indicator light on the main screen.)

When you shut down and restart Emerald Chronometer, it will start with the same skew value as it determined during the previous session, but it will also go get a new skew value in case it has changed since the last time the application was run. If the skew has changed (or if this is the first time the application has ever been run), then the hands showing the time will jump to the new correct value.

When the iPhone gets a new cell-phone time (for example, when it switches to a different tower), the iPhone OS changes its internal time base used by all applications, and sends a notification to running applications that the time has changed. When Emerald Chronometer gets this notification, it immediately changes the skew value by the amount that the internal time base has apparently shifted; it determines this shift by comparing against another internal time base that does not change with cell-tower changes (CACurrentMediaTime). Then it again goes out to the NTP servers to get the actual skew, which is typically quite close to the "educated guess". Occasionally, especially in fringe-reception areas, you will see the time indicator blink for a few seconds while it does this.

Notifications

Emerald Chronometer does not maintain NTP synchronization when it is running in the background. Therefore, if the iPhone's time base changes while Emerald Chronometer is not running, then alarm notifications for Istanbul and Thebes may be offset from their requested time. That can happen in a number of circumstances:

• The iPhone and the iPad 3G, if set to "Set time automatically", change their time base by a few seconds frequently when changing cell towers.
• If those devices turn off "Set time automatically", and for all other devices, the time is subject to the accuracy of the device's internal clock, which can be off by several seconds per day or more.

To minimize these small errors when relying on alarms, bring up Emerald Chronometer occasionally (long enough for the top-left light to become solid green); this will reset the time base used for alarms.

In addition, the OS does not guarantee that local notifications are delivered at the exact time specified; there may be a few-second delay if the device is busy with other activity.

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The Watches

                    

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Copyright © 2010, Emerald Sequoia LLC; last updated: 2010 June 11.

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Help Contents

Copyright Information

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Emerald Chronometer HD

Version 3.8

(click for full size image)

Emerald Chronometer HD is an iPad™ application that models 16 high-end mechanical watches.

• "Anyone with an interest in time and time keeping will want this must-have app for the iPad" —MacObserver

• "...beauty and sophistication..." —iPhone Life Magazine

Its functionally is nearly identical to that of Emerald Chronometer, which runs only on the iPhone^® / iPod^® touch.

Please see the Emerald Chronometer website for a detailed description of each of the watches.

Click on the image above to see a larger version as it would appear on an iPad.

FAQ

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Emerald Chronometer copyright info

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Website copyright © 2012, Emerald Sequoia LLC; last updated: 2012 Jun 16.

iPhone and iPad are trademarks of Apple Inc.

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Emerald Chronometer HD
FAQ

vs.

It crashes on the new iPad!

This bug is fixed in version 3.7.3 of Emerald Chronometer HD, which was released in the store on March 13. The crash only occurs on the new iPad with Retina display.

If you see a problem and you are running ECHD 3.7.3, please let us know immediately at essupport@emeraldsequoia.com. Note that we have not yet updated the graphics to fully take advantage of the Retina display, as that is a significant effort.

What's the difference between Emerald Chronometer and Emerald Chronometer HD?

• ECHD is for the iPad; EC is for the iPhone.
• ECHD runs only on iPad® and iPad 2®. EC runs on all iOS devices but on iPads it runs in emulation mode only.
• ECHD's options pages have been reformatted for the larger screen (though their function remains the same).
• ECHD runs in both landscape and portrait orientations.

The buttons at the bottom left and right don't work for me, although swiping left and right works fine.

We've had a few reports of this problem, all from customers running older versions of iOS (typically iOS 4.2.1). We have heard from them that upgrading to iOS 4.3.3 fixes the problem. (iPads that we own are all at iOS 4.3.x already and we've been unable to reproduce the problem with the simulator running an older version).

If you see this problem and you *are* running iOS 4.3.x, please let us know immediately at essupport@emeraldsequoia.com.

How come I have to pay again for the iPad version if I already have Emerald Chronometer?

The iPad version was a significant amount of work for us. For more details, see our blog entry about this. You might also be interested in why we code.

That's an awfully short FAQ. I have more questions.

Please see the Emerald Chronometer FAQ.

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Copyright © 2011, Emerald Sequoia LLC; last updated: 2011 May 5.

iPad, iPhone and iPod are trademarks of Apple Inc.

Home   Chronometer

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Emerald Chronometer Support

FAQ

I just see one watch and it's nothing like the screen shots on the App Store®.

Swipe left or right to see the others. Tap the "i" button to read the help files. Or click here.

I'm seeing crashes (Emerald Chronometer just abruptly disappears or hangs).

That was a frequent occurrence for many apps with early versions of the iPhone OS. If you're not running the latest version:
      http://www.apple.com/iphone/softwareupdate/
then upgrading may well fix it. And, of course, make sure you're using the latest version of Emerald Chronometer (at least 3.0). If you see a crash with the latest versions of Emerald Chronometer and iOS, and you're not running a jailbroken phone (see below), PLEASE report it to the email address below.

That said, in many cases, it will work if you just try again. You may have to turn the iPhone's power off and back on (hold down the sleep/wake button for a few seconds until you get the power off message). You may have to do this twice. If that doesn't fix it, the next step is to remove the app and download it again. Despite appearances, this will be free. Here are Apple's instructions for reloading an app:
      http://support.apple.com/kb/TS1702
It may be important to restore the app with iTunes® not with the App Store app on the phone itself. If your iPhone is nearly full (i.e. less than 10% free space as reported at the bottom of your phone's Info tab in iTunes) that may also cause problems. For additional tips that might help see:
      http://support.apple.com/kb/TS1295

Please contact us at the email address below if none of these suggestions help. We'll do our best to resolve your problem.

When a Local Notification is fired for an alarm when the app is in the background, the sound keeps going even after I dismiss the dialog.

This problem occurred on iOS 4.2 but was fixed with iOS 4.2.1 and iOS 4.3. Updating your device to the latest OS should fix the problem.

The alarm doesn't work if Chronometer is in the background or if the screen is locked (iOS 5 or later).

Go to the Settings app, choose the Notifications item on the left side, and scroll down on the right side until you see "Chronometer". Tap on it and then turn on the switch for "Sounds". That will allow the alarm sound to play even when Emerald Chronometer is not active.

Why did the app size increase so dramatically with Emerald Chronometer version 3.3?

Because of the larger artwork needed for the Retina display. For more details, see our blog entry about this.

The documentation claims it shows moonrise and set times but I don't see that anywhere.

Many features appear only on the "back" side of a watch. Click the button on the lower left corner of the screen to switch sides. (The moon rise/set info is on the backs of Haleakala and several others.)

Sometimes I see a miniature version of the watch for a second and it says "Loading". What does that mean?

It means we're reading the data describing that watch from secondary storage. That takes a while. We don't have enough RAM to keep all the watches loaded at once. We keep as many loaded as possible but if you swipe very quickly you can get ahead of our loader.

Firenze's back and the other watches don't seem to agree about rise and set times.

Right. And the Help is not entirely correct about when the planets are visible with respect to the horizon mask. Because Firenze only has a single horizon indicator for all of the planets (we use "planet" to refer to the Sun and Moon too, in this context), it is only a rough indication for any particular planet and can be wrong in certain situations; use Miami if you want precise information. Specifically, the horizon indicator shows only the azimuth of the intersections of the ecliptic plane with the horizon, and thus is only exact when read against the Sun hand (or against another planet's hand if the planet happens to lie exactly in the plane of the ecliptic). If the planet is outside the ecliptic plane (that is, if its ecliptic latitude is nonzero), then the horizon indicator for that planet can be wrong in two circumstances:
  * Close to the time of rise or set
  * Close to the time when the ecliptic plane passes through the zenith, as it does in tropical latitudes.
So the bottom line is that the horizon mask should be taken as a rough guide only. Use Miami if you want more precise info.

Mauna Kea shows the Sun in Cancer on Aug 3 but Cancer is June 23 – July 22.

It's because of the precession of the equinoxes and the inaccuracy of the calendar prior to the Gregorian Reform of 1582. Mauna Kea's zodiac dial shows the present astronomical positions of the constellations which have changed considerably from their positions when the astrological dates were fixed in ancient times. If you set the date back to about 600 BCE the constellations will be more closely aligned with the astrological dates.

But Mauna Kea doesn't seem to quite match the astronomical constellations, either.

Right. MK divides the zodiac into twelve equal sections and labels each one with a constellation. The actual constellations are not all the same size, so MK's labels are only approximate. The numbers in between each constellation label, however, do accurately indicate right ascension (measured in hours). Geneva's back side shows the actual constellation boundaries (for the present epoch).

Will it work on an iPod® touch?

Versions 1.1 and newer support the iPod touch. But see here for more about setting your time and location correctly.

Will it work on an iPad®?

Yes. It will work just as it does on the iPhone, there's no special iPad version (yet).

It doesn't look quite the same on my iPhone 4 as the pictures on the website.

Right. There are separate high-resolution graphics for the Retina display. Here's an example.

Will Emerald Chronometer work without an Internet connection (eg. out in the wilderness where even cell phone service is unavailable)?

Yes. Time and location are all that we need; all of the astronomy calculations are done internally with no Internet required. See here for more about setting your time and location correctly.

The sunrise/sunset times are wrong on my iPod touch.

You may need to enter your latitude and longitude manually. You do this via the Settings panel which is accessed from the "gear" button in the lower right corner of the screen. See here for more details.

Will it work on a jailbroken iPhone?

Probably not. We don't support that configuration and we've had reports of odd problems.

What's all this about "complications"? What's so complicated about a little calculation?

Well, the calculations are actually pretty complex. But "complication" is a term of art in the horology (fancy watch) world. It refers to any watch display other than hours, minutes, and seconds (or sometimes simple day/date). See:
      http://en.wikipedia.org/wiki/Complication_(horology)
Emerald Chronometer has a very large number of complications; here's a list.

The times for moonrise and moonset are not consistent between the various watches.

Emerald Chronometer uses different rules for the "ring"-type displays like Mauna Kea and for the "dial"-type displays like Haleakala:

The "dial"-type displays use rise and set times for the current day (i.e. the day shown in the date windows), except in cases when the event doesn't happen on that day in which case it just displays 00:00 (this happens a couple times a month for the Moon and in summer and winter at high latitudes for the Sun). The values are updated at midnight.

On the "ring"-type displays, we use a more complicated algorithm but the result is simpler. The rings show the closest rise and set time to the current time without regard to the day or whether that's before or after the current time. (In detail: if the Sun is above the horizon then the sunrise indicator shows the time of the previous sunrise and the sunset indicator shows the next sunset; but if it's nighttime then the sunset indicator is shows the time of the last sunset and the sunrise indicator shows the time of the upcoming sunrise. The sunrise time is updated at sunset and vice versa. Similarly for the Moon.)

Since the times of sunrise and sunset change by only a few minutes per day the differences between the two rules are small. But the times of moonrise and moonset change by about an hour each day so the differences are readily apparent.

Watch	Side	Rule	Values
Mauna Kea	both	Ring	next/prev
Haleakala	both	Dial	for day
Geneva	front	Dial	for day
Geneva	back	Ring	next/prev
Miami	front	Ring	next/prev
Miami	back	Dial	for day
Vienna	both	Ring	next/prev

I set Haleakala's time to the exact time of sunrise but the altitude hand is a little below zero.

Yes, that's right. Sunrise is defined to be the time at which the first bit of the Sun's disk is visible. But the Sun's altitude is defined as the altitude of the center of the disk. It takes several minutes for the Sun to move that far.

I have a real watch that displays the Equation of Time. It shows a value that's not the same as yours.

We adopt the convention that a positive number means the sundial will show a later time than an ordinary clock. IE:
      EOT = sundial time - standard time
Some watches use the opposite convention. Learn more about the Equation of time here:
      http://en.wikipedia.org/wiki/Equation_of_time

I leave my iPhone in its dock to charge and love to see my watches all the time. But how can I do that without disabling Auto-lock completely?

Emerald Chronometer has two settings that allow you to disable Auto-lock while it is running: one that applies when the device is plugged in and another that applies when running on battery power. Be careful with the second one; it can drain the battery in just a few hours. See here for more details.

I set an alarm and quit Emerald Chronometer but when the alarm time came no alarm rang. This works fine with the builtin Clock and Calendar apps.

In iOS 4 and above, Emerald Chronometer will deliver a local notification in this case. If your phone can't run that OS because it's too old, there's nothing we can do for you; in older OSs, Apple didn't allow any third party apps to do anything in the background.

When my alarm goes off when the screen is locked shaking doesn't silence it.

Yes. Apple disables the accelerometers when the screen is locked. We have no control over this. The alarm will stop when you unlock the screen.

I set an alarm and left Emerald Chronometer running but when the appointed time arrived in the morning there was no sound.

In some cases with the iPod touch the volume gets reset to zero. After considerable research one of our customers (using OS 3.1.2 on a new iPod touch) describes it this way: "I now suspect a flaw in Apples's software. If Calendar or Mail prefs call for no sound and an event occurs, the apps instruct iPod's master volume to set to zero. Since other apps assume the volume is previously set as the user wishes, no sound is subsequently produced when those apps trigger an event. No doubt the unintended consequence of the new coding necessary to accommodate the physical volume controls....I have been able to confirm that no non-apple alarm clocks function, now. The OS is buggy in the sound department. Forums are full of complaints about all kind of sound issues."

When I start up Emerald Chronometer sometimes the hands jump just as the time synchronization indicator turns green.

Yup. Until we get the first reply from an NTP server we don't really know what the right time is. It will be stable after that.

My eyes aren't what the used to be and some of those dials and hands are awfully small. Can you implement a zoom feature?

Recent iPhone and iPod touch models have a way to do a zoom on any app. Go to Settings=>General=>Accessibility and click on Zoom. The zoom gestures are explained on that page. If you don't find this setting, make sure you have the latest iPhone OS.

Why is it asking to use my location?

Emerald Chronometer needs to know your location in order to compute various astronomical quantities (eg. sunrise time). That's all we use it for. The data is stored on your device only. We do not transmit it anywhere. We do not sell it to anyone. We update it each time the app starts up and about once an hour thereafter. It will be copied to your computer when you sync with iTunes so you may want to encrypt your backups.

Since I bought Emerald Chronometer, I've started getting spam about watches!

Emerald Sequoia has not ever sold, nor will we ever sell, email addresses of our customers or of anyone else who contacts us via email. We hate spam as much as you do.

I'd love to have Emerald Chronometer running on an iPod nano, say with a TikTok or LunaTik watch band.

We'd love that too! But unfortunately Apple doesn't allow third-party developers to write apps for the nano; it's not running iOS like the iPhone and iPod touch.

If and when Apple does open up the nano to third-party apps, you can be sure we'll be taking a look....

It sure would be nice if ...

Don't hesitate to send us enchancement requests or ideas for new watches. Some of the ideas we've gotten have been really interesting! We're only a two-person company, so we can't promise if or when any particular request will be implemented. But the more requests we get from our customers for a particular feature the higher its priority becomes. Unless we think it's really cool and do it right away.

The iPhone isn't designed for the wrist! How can I get the full experience of actually wearing a fine mechanical timepiece?

If you're desperate, you could try this.  But we don't recommend it.

I thought upgrades were free but the App Store seems to have no option other than "Buy Now".

Yes, that's a bit odd. But it really is free. Just click the "$4.99" button and the "Buy Now" button and enter your password. After a bit you'll see a message saying, "You have already purchased this item. To download it again for free, select OK."

I tried to upgrade to the latest version and got a message saying I needed to pay again. I thought the upgrades were free?

This is most likely the result of a mix up in your iTunes configuration. It probably doesn't recognize you as the one who bought the original version, perhaps because you have more than one iTunes account.

It may also be that the account you used with the App Store app on your iPhone is not the same as the one you're using with iTunes. If so, and you don't want to change that, then just get the upgrade directly on your iPhone via the App Store application.

I want my money back <for whatever reason>

Unfortunately, Apple does not provide developers like us a way to refund or annul a purchase, as far as we've been able to discover. One thing that may work, though, is to use the iTunes® store feedback process described at
    http://support.apple.com/kb/HT1933
One of the great benefits of the way Apple set up the iPhone application distribution system is that developers don't have to get involved in the billing process. One of the negatives is that we have no direct way to help even if we want to.

Bugs

We work hard to make Emerald Chronometer as close to perfect as we can. But we're realists. And we're here to help. So if you have a problem just send mail to

essupport@emeraldsequoia.com

Please read the documentation and check the FAQs first. Make sure you have the latest version (see the Release Notes); it's displayed at the bottom of each Help screen. We try to respond quickly but we're only a two-person company so occasional delays are inevitable.

Feedback

We would also very much appreciate any comments you may have about how we can improve Emerald Chronometer in the future. In particular, we will be making more watches. We would love to hear your ideas. Use the email address above.

Release Notes

Click here to see what's changed in each release.

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Copyright © 2011, Emerald Sequoia LLC; last updated: 2012 Jan 11.

Apple, iTunes, App Store, iPhone and iPod are trademarks of Apple Inc.

Home   Chronometer   Support

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The Emerald Wristwatch

Use a new rubber band. Emerald Sequoia will not be held responsible for damage to your iPhone from use of this idea. Nor for medical expenses if it cuts off the blood to your hand. Nor for damage to your reputation if anyone actually sees you this way.

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No copyright Emerald Sequoia LLC; last updated: 2009 April 2.

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Emerald Chronometer

Version 3.8

Emerald Chronometer^® is an iPhone™ application that models high-end mechanical watches. These models contain many of the most complex "complications" found in real watches, plus refinements found nowhere else. All displays maintain the look and feel of real mechanical objects, but with the time and location accuracy of the iPhone.

• "App Store Pick of the Week" in July 2008

• Apple "Staff Favorite" in December 2008
• 
• 
• 
• "Absolutely the most beautiful graphical software application of any kind that I've ever seen."

Clock Features:

• Local, UTC time
• Day/date/month/year indicators, using mechanical wheels
• World-time watch with 24-city ring on one side and 4 subdials on the other
• Chronograph (stopwatch) with split timer
• Alarm clock and interval timer
• Most watches with 1/5 sec or 1/10 sec precision
• Synchronized with standard atomic clocks via NTP

Astronomy Features:

• Highly accurate data from 4000 BCE to 2800 CE
• Rise and set times for the Sun, the Moon and the 5 classical planets including a unique face showing the rise and set times of all 5 classical planets plus the Sun and the Moon at once
• The correct shape and orientation of the Moon in all phases but still using a mechanical display
• Relative positions of the Sun, Moon, 6 planets and the constellations of the zodiac
• Times of the solstices, equinoxes and apsides; position of the Earth's terminator
• Eclipse predictor (lunar node indicators and separation indicator)
• The correct shape and orientation of the Moon in all phases but still using a mechanical display
• Relative positions of the Sun, Moon and the constellations of the zodiac
• "Compass functions" show the elevation and azimuth of the Sun, the Moon and 5 planets; twilight times
• User settable geographic location and timezone using an 80,000 city database
• The Equation of Time, solar time and sidereal time

Please see Emerald Chronometer HD for the iPad™ version of this app.

The following links describe Emerald Chronometer and its watches in more detail:

The Application

• Controls and Notes
• Options settings
• Time Synchronization
• The Complications
• Accuracy of the Astronomical Algorithms
• Predicting Eclipses
• The Physics of Emerald Chronometer
• Release Notes

The Watches

• Alexandria, a mini-planetarium
• Atlantis, iPhone steampunk
• Chandra, all about the Moon
• Haleakala, rise and set complications
• Mauna Kea, timekeeping's astronomical roots on display
• McAlester, an old pocket watch
• Paris, simple, elegant
  
  
• Geneva, classic multi dial with many complications
• Istanbul, alarm
• Olympia, chronograph (stopwatch)
• Thebes, countdown timer
  
  
• Firenze, heliocentric orrery
• Miami, rise/set times and other info for each planet
• Vienna, 24-hour time
  
  
• Terra, world time with customizable cities
  
  
• Babylon, full-month calendar
  
  

Customer Support and FAQ

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Emerald Chronometer copyright info

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Website copyright © 2012, Emerald Sequoia LLC; last updated: 2012 June 15.

iPhone is a trademark of Apple Inc.

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The Physics of Emerald Chronometer

Emerald Chronometer is designed to be a realistic depiction of a mechanical watch on an iPhone. Considerable care has been taken to avoid displaying things that are physically impossible, to enhance the illusion that you're looking at a real mechanical time piece.

For example, the moon phase display on the watch named Chandra (above right), while considerably more realistic than a typical moon-phase clock or watch (because it shows the correct shape for all phases), is implemented with leaves that move to cover the display rather than simulating a picture. And the black-and-white day/night indicators in the watch named Mauna Kea (above left) are implemented as white ring-segments that rotate into place over the black background. If you look closely you can see the faint borders of these segments move as you press and hold down over the date window with the crown disengaged (you may need to move the hands out of the way first).

You'll see examples of this throughout the application. Pieces on watches don't move without some visible means of support, and date wheels slide into place instead of just flashing to their new number. The watches are designed to have the look and feel of something actually mechanical.

Of course, Emerald Chronometer has no gears behind the covers turning those wheels and hands. A real mechanical watch implementing Mauna Kea would be on par with, if not more complicated than, the most complicated watches available today. Real mechanical watch designers live in a much different world, and the authors of Emerald Chronometer have great respect for the miracles they are able to accomplish with microscopic mechanical parts. Further, Emerald Chronometer has access to two things mechanical watches don't, an accurate time source (atomic clocks via the Internet) and accurate location data (from the iPhone's Location Services).

So Emerald Chronometer is somewhat of a hybrid: a simulation of a mechanical machine which, under the covers, does a bit of the impossible. It's a magic trick in reverse, if you will, where the bit that seems impossible is behind the curtain instead of in front of it. The authors hope you enjoy the effect.

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The Watches

                    

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Copyright © 2009, Emerald Sequoia LLC; last updated: 2009 November 25.

NTP Copyright Notices

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Some of the code in Emerald Sequoia apps is subject to the following copyright notices:

***********************************************************************
*                                                                     *
* Copyright (c) David L. Mills 1992-2007                              *
*                                                                     *
* Permission to use, copy, modify, and distribute this software and   *
* its documentation for any purpose with or without fee is hereby     *
* granted, provided that the above copyright notice appears in all    *
* copies and that both the copyright notice and this permission       *
* notice appear in supporting documentation, and that the name        *
* University of Delaware not be used in advertising or publicity      *
* pertaining to distribution of the software without specific,        *
* written prior permission. The University of Delaware makes no       *
* representations about the suitability this software for any         *
* purpose. It is provided "as is" without express or implied          *
* warranty.                                                           *
*                                                                     *
***********************************************************************

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
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/*
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 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
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Emerald Chronometer HD

Los Gatos, California, May 7, 2011.  Emerald Sequoia LLC today released Emerald Chronometer HD, an iPad version of its highly rated Emerald Chronometer iPhone app, in conjunction with a 60% price reduction in the iPhone app, which is now about USD$2.

Both apps model running 15 mechanical watches, with very fine precision and an emphasis on astronomical complications.  Emerald Chronometer was Apple app of the week  in July 2008, an Apple "Staff Favorite" in December 2008, and was rated the BEST clock app at appreview.com, and has been improved continually since it was first introduced.  Both apps are available now at the app store (Emerald Chronometer HD, Emerald Chronometer).

Emerald Chronometer HD is functionally identical to Emerald Chronometer, except that it takes full advantage of the increased resolution of the iPad, and runs in landscape mode there. You can find high-resolution screen captures of Emerald Chronometer HD here, and a full description of all of the functionality included in both apps on Emerald Chronometer's website here. Both apps include a full copy of this website as in-app Help, which has been described by a reviewer as the best Help system available for any app.

 

Emerald Sequoia LLC

Emerald Sequoia LLC is a two-person company whose combined experience in software development is over 55 years, and which has been involved with iPhone app development since the first beta development kits were available from Apple in the spring of 2008.

 

iTunes app store links:

Emerald Chronometer HD
Emerald Chronometer

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Emerald Geneva 1.0

Los Gatos, California, December 28, 2009.  Emerald Sequoia LLC today released Emerald Geneva, a Lite version of its critically acclaimed Emerald Chronometer iPhone app, following closely an update of Emerald Chronometer to version 3.0.  Both apps model a running mechanical watch, with very fine precision and an emphasis on astronomical complications.  Emerald Chronometer was Apple app of the week  in July 2008, an Apple "Staff Favorite" in December 2008, and was rated the BEST clock app at appreview.com.  Both apps are available now at the app store (Emerald Geneva, Emerald Chronometer).

 

Emerald Geneva

Emerald Geneva, with an introductory price of $0.99 in the US, models the watch Geneva, designed by Emerald Sequoia LLC, which is the most complicated of the 14 watches shipped with Emerald Chronometer.  Geneva has the following features:
- NTP (atomic time) synchronization
- Sunrise/sunset and moonrise/moonset dials
- Moonphase
- Perpetual calendar
- Eclipse predictor
- Ability to quickly set watch to any date from 4000 BCE to 2800 CE
- Location setting with four ways of setting location and timezone
- Zodiac constellations
- Lunar node indicators
- Sidereal time
- Precession of the equinoxes
- Right ascension of Sun and Moon

 

Emerald Chronometer 3.0

Emerald Chronometer includes Geneva and 13 other watches, and has been available since the App Store opened in July 2008.  Version 3.0 of Emerald Chronometer, released earlier this month, adds displays for the positions of the 6 inner planets (through Saturn), a new grid mode that shows multiple watches running simultaneously, and a sophisticated location-setting system with four ways of setting your location and timezone.  The image above shows just one of the new watches (out of a total of 14 now included).

The help system describing all of these watches has been described by a reviewer as the best Help system available for any app.  A copy of that help system, which also includes a 5-minute demo movie just scratching the surface of the functionality, can be found at the Emerald Chronometer web page

 

Emerald Sequoia LLC

Emerald Sequoia LLC is a two-person company whose combined experience in software development is over 55 years, and which has been involved with iPhone app development since the first beta development kits were available from Apple in the spring of 2008.

 

iTunes app store links:

Emerald Chronometer
Emerald Geneva

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Emerald Observatory 1.0

Emerald Hills, California, 2010 April 03. Emerald Sequoia LLC today released Emerald Observatory, a complex clock application for Apple's iPad aimed at amateur astronomers, photographers and anyone with an interest in time and the solar system:

(click for full size image)

In addition to ordinary time and date, Emerald Observatory displays a wealth of astronomical information all on one screen, in a unique but understandable format. Information includes:
- Times of rise and set for the Sun, the Moon, and the 5 classical planets
- Times of the beginning and ending of twilight
- Heliocentric orrery (display of the planets in orbit around the Sun)
- Altitude and azimuth for the same bodies (one body at a time)
- Current phase and relative apparent size of the moon
- Current regions of day and night on a world map
- The Equation of Time, solar time, UTC time, and sidereal time
- Month, day, year, and leap-year indicator
- Displayed times are synchronized via NTP to "atomic clock" standard
- Uses iPad location, or the latitude and longitude may be set manually
- Option to force the display to stay on continuously

The time can be set to any date from 4000 BCE to 2800 CE. The clock can be animated at high rates to more easily see the changes in long term astronomical variables such as the seasons and moon phases. A detailed description manual for the operation of Emerald Observatory can be found at the Emerald Sequoia LLC web site at http://emeraldsequoia.com/eo/. Emerald Observatory is priced at just $0.99 and is available now at Apple's App Store here.

(Full size image available on request.)

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Emerald Sequoia LLC Press Releases

	Emerald Chronometer HD (May 7, 2011)
	Emerald Observatory 1.0 (Apr 3, 2010)
	Emerald Geneva 1.0 (Dec 28, 2009)

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The iPhone Flashlight

Download one of the images below to your computer and copy it to the Photo library on your iPhone. Then when you need to see in the dark just display the image with your iPhone's Photo application. To change the brightness just zoom and scroll the image! The astro version makes a red flashlight that is less damaging to your dark adaptation. Both are free.

white version

astro version

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Copyright © 2008, Emerald Sequoia LLC; last updated: 2008 July 07.

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Emerald Timestamp

Version 1.0

Copyright © 2010 Emerald Sequoia LLC, all rights reserved.

NTP code derived from public domain sources covered by these copyrights.

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Copyright © 2010, Emerald Sequoia LLC; last updated: 2010 May 9.

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Moving Events From One Device To Another

Please note: Emerald Sequoia LLC does not endorse or support the following procedure. We offer it as a possibility for those customers who really want existing events on a different device, and who no longer need events that may have already been captured on that other device (merging is not possible).

There is no supported way to move events from one device to another. However, some people have had success using a 3rd-party program (not affiliated with Emerald Sequoia LLC) called PhoneDisk for the Mac. Please use this procedure at your own risk, and follow the suggestions to back up your devices and your data before starting. And please note that existing events on the destination device will be lost!!!

1. Make sure Emerald Timestamp is installed on both devices.
2. Back up both devices using iTunes.
3. Use Emerald Timestamp on each device to email yourself a copy of all events, so you have them in some format in case something goes wrong.
4. Obtain a copy of the Mac program Phone Disk, and install it on your Mac. At this writing, it can be found at http://www.macroplant.com (Note again, this is not our product).
5. If the destination device is running iOS 4.0 or later, reboot it (this will ensure that Timestamp is not running in the background and thus will not collide with the changes we will be making).
6. Connect the device containing the events to be moved to the Mac.
7. Wait a minute or so for Phone Disk to recognize it, then from the Phone Disk menu, select the device name, and then "Change Connection Root" => "Timestamp".
8. If Phone Disk is working properly, it should mount a virtual disk on your Mac with the name of your device. Navigate there; you should see several subfolders, including "Library" and "Documents".
9. Navigate to Library => Preferences. You should see a file called "com.emeraldsequoia.Timestamp.plist". Copy that file somewhere on your Mac.
10. Now connect your second device to the Mac (the one you want to copy the Timestamp events to).
11. From the Phone Disk menu, select the second device name, and then "Change Connection Root" => "Timestamp". (If Timestamp is not there, ensure you've installed Timestamp on the device, and then retry).
12. A new virtual disk should show up on your Mac with the name of your second device.
13. On that new virtual disk, navigate to Library/Preferences. Again you should see the file "com.emeraldsequoia.Timestamp.plist". You'll be replacing this file with the one you copied from the other device; you may want to copy the existing one somewhere on your Mac first (note: It is not possible to merge two event lists; any existing events on this device will be lost!).
14. Copy the other device's file from where you copied it in step 9 into the new virtual disk's Library/Preferences folder.
15. Now start Timestamp on the new device. You should see the same events that are shown on the old device. Again, your existing events on the new device will be lost.

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Copyright © 2011, Emerald Sequoia LLC; last updated: 2011 Aug 22.

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Emerald Timestamp Release Notes

Version 2.0.4_g38aa128 (2012 Sep 19)

• Further support for iOS 6
• Landscape orientation supported in detail panel

Version 2.0.3_gd1ff2be (2012 Aug 13)

• Support for iOS 6
• Tweak help text

Version 2.0.2_g2fe80aa (2012 May 23)

• Relax constraint for "green" events to 0.40 seconds to account for more thorough error analsysis introduced in v2.0, and make it a user-settable option
• Add option for which time formats are cycled through
• Change method of reporting intervals that span a DST (summer time) event ("days" now are considered to be 24-hour intervals in all cases)
• Better reliability when synchronizing via unreliable network

Version 2.0_gd984f13 (2012 Apr 19)

• Custom predefined event names with buttons for each
• Live display of and capture of events during leap second (e.g., 23:59:60.3 UTC)
• Delete multiple events at once without clearing entire list
• Landscape mode on iPhone for most screens
• Settings (options) are now done in-app
• Smaller footprint on NTP pool hosts
• Option to control whether time or description is on top of each event row
• First letter of event description automatically capitalized (if auto-capitalization is turned on for device)
• Option for multiple zero reference points
• Fix bug in max-events email setting

Version 1.4_g4722fad (2011 Apr 16)

• New option in Settings app to display JD dates in TT or UTC form
• Fix crash attempting to mail a long list of events

Version 1.3.4_r322 (2010 Dec 31)

• Fix year display (was showing 2010 instead of 2011)

Version 1.3.3_r313 (2010 25 Nov)

• Fix bug where unqualified event results in mailed events missing accuracy column

Version 1.3.2_r306 (2010 20 Nov)

• Support iOS 4.2
• Fix timezone name on local times of events recorded during a different DST period

Version 1.3.1_r294 (2010 4 Aug)

• Don't refresh everything on the event page when the sync fails, to avoid resetting in-progress edits
• Reject sync with a negative uncertainty

Version 1.3_r276 (2010 8 Jul)

• New interval display mode which can show the difference in time between any two events
• Optional tick sound
• Improved images for iPhone 4

Version 1.2_r224 (2010 17 Jun)

• Optimized for iOS 4
• New options in Settings app for email format and limits

Version 1.1_r206 (2010 19 May)

• Current accuracy display now on main page; tapping it gets a new sync
• Fix missing AM/PM in app's 12-hour mode when device is in 24-hour mode
• Synchronization now tries again much sooner after a network-unavailable failure.
• Workaround for some cases where device auto-lock setting is ignored
• Mailing events now uses built-in message composer instead of switching to Mail

Version 1.0.1_r174 (2010 May 09)

• Initial release

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Copyright © 2010, Emerald Sequoia LLC; last updated: 2012 September 23.

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Emerald Timestamp

Version 2.0.2

Emerald Timestamp lets you capture the precise times of events, and associate a description with each one. It's a universal app which runs at full resolution on the iPad, iPhone, and iPod touch.

Press the large button with the arrows pointing down to record the current time value. It will show up at the top of the list below. Add as many as you like; the list scrolls.

To add a one-line description, tap an event in the list and enter the description on the detail page (see below).

Tap the date or time at the top of either screen to change the format of the time displays. Each tap cycles between 12-hour local, 24-hour local, UTC (aka GMT), Julian Date (an astronomical time reference; see below), and "interval" times (see below). You can choose a subset of these time formats to be cycled through using the Options panel (see below).

To find the difference in times between events, switch to "interval" display (see above) and then tap the "zero" button on an event in the list, and other times will be measured against that zero reference. Equivalently, press the "Use as reference zero" button on the detail page for an event. The behavior is different depending on whether the option "Allow multiple interval zeroes" is turned on (see below):

• If off (the default), then a single reference zero is used for all events, and events prior to the designated zero are displayed with negative interval times.
• If on, then intervals are always measured forward from the previous zero, and the first (oldest) event is always a zero event.

To go back to absolute times, tap the main time display at the top until your desired time base is displayed.

Options (Settings) are available via the Options button at the bottom center. On the Options screens you can

• Create custom event-capture buttons, which preload the captured event with a string you can define (the string also appears as the button title)
• Disable the device's Auto-Lock function so that it won't lock the screen while you're waiting for an event to occur
• Disable the button click sound
• Select which time formats are included in the cycle when tapping on a date or time. Note that there are two Julian Date (JD) formats, depending on whether the JD displays are referenced to UTC or to TT. The latter is preferred for astronomical measurements (see Wikipedia) but the default is UTC to be consistent with older versions of Emerald Timestamp. Each timestamp indicates the current global setting (i.e., "JD (UTC)" or "JD (TT)").
• Select the threshold of error bound which results in green buttons and events (see below)
• Specify that email should be sent with tab separated values (TSV) instead of plain text
• Limit the number of days and events sent when emailing "All events".
• Specify that there can be multiple zero points for intervals.

The iPhone's internal clock can be somewhat unreliable. So when Emerald Timestamp starts up (and every time it is awakened after the device has been locked) it uses NTP to synchronize its own clock with the international standard atomic clocks. This process requires network access and can take several seconds. Until it is done the accuracy of event timing is somewhat uncertain. During that uncertain time, Emerald Timestamp's big button is yellow. When the sync is complete, the button turns green and event timing is very accurate.

Emerald Timestamp uses location services to determine the best time servers to contact. Time servers that are in the same country will generally result in faster round-trip times and thus better accuracy and faster synchronization.

You can record events even when the button is yellow. If a sync is completed before the app is shut down or the device is locked, then the sync will be applied retroactively to all events captured since the last startup or unlock (and the displayed time values for such events may change as a result). The green/yellow indicator light to the left of each event indicates its time accuracy.

Tapping an event in the list brings up a page showing more detail about that event. You can add a one-line description by tapping the "Event description" field. You can email this event's details or the details of all the events.

The detail page also shows an accuracy bound for the time of the event. The accuracy of synchronized events is primarily constrained by the length of time it takes for a round trip from the device to the NTP server and back; server times are usually much more accurate than that round-trip time. Emerald Timestamp reports the accuracy based on that round-trip time, refined by a number of request-report cycles, and including an estimate of the server error based on its own reported parameters.

A synchronization is considered "green" by default if its reported accuracy is less than 0.40 seconds; this threshold may be set in Settings (see above). In "interval" mode (see above) both events must have an accuracy less than the specified accuracy for the interval to be green; the detail page reports the actual combined accuracy (which may not be larger than an individual event's accuracy if the app session was running continuously between the two events). Regardless of the threshold chosen, Emerald Timestamp continues to refine the synchronization until the error is no more than 0.16 seconds, or until it times out trying (after a minute or two).

At the top right of the main screen is an indicator of the current accuracy bound. It's gray while synchronizing, and white at other times. Tap it to force another synchronization.

Press the Edit button in the lower right to remove one or more events from the list. The button at the lower left starts out as "Delete All", which will remove all events at once; or you can tap individual events to select them and then tap the lower-left button, which will be labeled "Delete (n)" where n is the number of events that will be deleted.

This version of Emerald Timestamp has tentative support for live leap-second display. See this page for details.

Customer Support

Release Notes

Copyright information

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Website copyright © 2010, Emerald Sequoia LLC; last updated: 2012 Feb 4.

iPhone is a trademark of Apple Inc.

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Support for Leap Seconds in Emerald Timestamp

Beginning with version 2.0, Emerald Timestamp has tentative support for live leap-second display. That is, during the insertion of the leap second at the end of June 2012 (UTC), the UTC time read, for example,
23:59:59.9 UTC
23:59:60.0 UTC
23:59:60.1 UTC
23:59:60.2 UTC
...

You can see a movie of Emerald Time and Emerald Timestamp taken during the leap second in June 2012 here.

A few notes about this support:

• Intervals that span a leap-second event are properly calculated.
• NTP servers in the past have not been consistent in returning the correct time after a leap-second event, so the time may revert (or partially revert) when the first sync comes in following the event. It will eventually catch back up to the official time as the NTP servers correct themselves properly, so this will only affect times captured during the period immediately after the leap-second event.
• JD(UTC) will "hold" at the leap-second boundary, because it has no way of representing the intervening time. This is why JD(TT) is recommended to be used in its place, though of course it is referenced to a different standard.
• Similarly, Excel has no way of representing the extra time, so when exporting to an Excel spreadsheet the times like :60.x are represented as being at :00.0 for the next minute. Excel-format intervals are correctly exported.

NTP Copyright Notices

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Some of the code in Emerald Timestamp is subject to the following copyright notices:

***********************************************************************
*                                                                     *
* Copyright (c) David L. Mills 1992-2007                              *
*                                                                     *
* Permission to use, copy, modify, and distribute this software and   *
* its documentation for any purpose with or without fee is hereby     *
* granted, provided that the above copyright notice appears in all    *
* copies and that both the copyright notice and this permission       *
* notice appear in supporting documentation, and that the name        *
* University of Delaware not be used in advertising or publicity      *
* pertaining to distribution of the software without specific,        *
* written prior permission. The University of Delaware makes no       *
* representations about the suitability this software for any         *
* purpose. It is provided "as is" without express or implied          *
* warranty.                                                           *
*                                                                     *
***********************************************************************

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * Copyright (c) 1982, 1986, 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

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Emerald Timestamp Support

FAQ

Sometimes my device locks even though "Disable auto-lock" is set for that configuration.

This is a known issue with the mechanism used by Emerald Timestamp to disable auto locking; sometimes the device fails to honor the request. We have strong evidence that this is an Apple OS problem and have submitted a bug report to Apple.

Will it work on an iPhone™ or iPod® touch or iPad™?

Yes. Emerald Timestamp is a "universal" app. Buy it once and it will run on all your iPhone OS devices, at full resolution.

Will it work on a Mac or a PC or any other smart phone?

No.

Will Emerald Timestamp work without an Internet connection?

Yes. But the accuracy of the times cannot be guaranteed.

When the button goes from yellow to green sometimes the time values change.

The time of the event didn't change. What changed is Emerald Timestamps's clock against which the event times are measured. The new time is more accurate.

What's does JD mean?

"Julian Date". It's for astronomers.

Bugs

We work hard to make Emerald Timestamp as close to perfect as we can. But we're realists. And we're here to help. So if you have a problem just send mail to

essupport@emeraldsequoia.com

Please read the documentation and check the FAQs first. Make sure you have the latest version (see the Release Notes); it's displayed on the Help screen. We try to respond quickly but we're only a two-person company so occasional delays are inevitable.

Feedback

We would also very much appreciate any comments you may have about how we can improve the Emerald products in the future. We would love to hear your ideas. Use the email address above.

Release Notes

Click here to see the release notes.

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Copyright © 2010, Emerald Sequoia LLC; last updated: 2010 Aug 13.

iPhone, iPad and iPod are trademarks of Apple Inc.