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Apple's Kevin Lynch Explains Method Behind Apple Watch's Precise Timekeeping

bobob said:
Since you're making the extraordinary claim that Apple is lying about the 50ms accuracy of the Apple Watch, and that you witnessed one running 240x faster, then I consider it your responsibility to support your contention with evidence. :)
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Actually, it makes sense that at least some Apple Watches in a store would be off.

Normally an iPhone can only sync with a single Apple Watch at a time, and vice versa.

So, unless they have special software, it'd be a pain to keep dozens of display devices constantly updated.

--

Also, it's not running 240x faster, of course :D I think you meant to say that it was 240 times less accurate than the claim of 50ms if it were constantly sync'd.

Maybe it's been running without a time sync since last June. Or maybe it was last sync'd 24 hours ago. We just don't know.
 
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kdarling said:
Actually, it makes sense that at least some Apple Watches in a store would be off.

Normally an iPhone can only sync with a single Apple Watch at a time, and vice versa.

So, unless they have special software, it'd be a pain to keep dozens of display devices constantly updated.
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Indeed yes, it does, as you say Make Sense if the apple watch is, in reality a pretty inaccurate device, and needs to constantly be corrected/put right by an outside source.

Hence why someone might have a issue with the LARGE BOLD text on Apple's website:

"At its heart, an incredibly precise timepiece."

If it's only shows the right time because something else keeps telling the watch the right time, then I don't see how you really can say that above BOLD statement is genuinely truthful.
 
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bobob said:
Since you're making the extraordinary claim that Apple is lying about the 50ms accuracy of the Apple Watch, and that you witnessed one running 240x faster, then I consider it your responsibility to support your contention with evidence. :)
Click to expand...
I was not trying to claim that Apple were lying but answering a question that another member had just asked (which I also quoted).

Apple are only claiming the watch is accurate to that high level when it's being regularly synced to their time servers via it's owners iPhone. As the display models are not able to sync to the time server under their own steam there is a good chance they won't display the same accuracy.

My anecdotal observation doesn't prove or disprove anything because we have no idea when the last time sync had occurred. It could have been the night before which would mean the watch isn't very accurate on it's own or it could have been weeks before when the display was set up, meaning it's accuracy is pretty damn good.

I would have great difficulty taking a photo of the app displayed on the iPhone sitting next to the watch when the only camera I carry while out shopping is located on the iPhone itself. As I have no intention of carrying a SLR camera on my shoulder the next time I go out shopping I'm afraid you will have to take my word for it this time. :p
 
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CarlJ said:
Yes, they're consumer level watches. What in the world does that have to do with NTP synchronization? A hammer is also a consumer level product. It also does not sync time using NTP. I quite clearly said I was happy that there was a consumer level watch available that syncs time via NTP. The Casio Waveceptor syncs time several times a day by listening for a radio signal. It often does not receive the signal, and just... keeps running with its best guess of the time. Go read the FAQs for the watches, they say it's best to not have them in a building, or to put them in a window (with the watch oriented towards the direction of the transmitter tower), to get the syncing to work. It's an iffy thing. I have a Casio G-Shock Solar that works the same way. Sometimes it syncs. Often it doesn't. If the reason for syncing it to be assured you have the correct time, there's no point in having a watch that maybe syncs sometimes - because you can't be assured it has the right time. And there is no feedback loop between client and server to actively account for the transmission/reception delay, something which the NTP protocol properly handles.

In order to sync, the Apple Watch needs a good Bluetooth connection to the phone, and the phone needs a decent network connection (wifi or cell). I'd wager most Apple Watch users have both of these almost all the time. There's no "well, I should put it in the window pointing north east at midnight to maybe get the time". It just happens.

To be clear:
To be assured of the correct time with the Apple Watch (yes, assuming it's charged - I haven't found that to be a problem):
1. Look at the watch's display and read the time.

To be assured of the correct time using a Casio Waveceptor:
1. Look at the watch's display and read the time.
2. Wonder when the last time was that it successfully received a time signal.
3. Push some buttons to check the last time it synced correctly (mine will show the date last synced), and decide if it was recent enough for the watch's notion of time to be reasonably accurate.

To be assured of the correct time using most other watches:
1. Look at the watch's display and read the time.
2. Wonder when the last time was that you set the time on the watch (and how accurately you set it).
3. Decide if it was recent enough, or if you should look around for some other more trustworthy time source.

I strongly prefer the one-step Apple Watch / NTP way. I like that I can glance at the watch and "know" the time with a high degree of reliability (since the prerequisite network connections are basically always there).
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NTP specifically, no. Time synchronization, yes. And without an iPhone, cell signal, and active Bluetooth link to boot. A decent quartz watch can be around +- 15 seconds per month so why the obsession with constant NTP or radio updates? It might be fun to talk about but it matters to just about zero people's lives.

I have another fitness device that updates it's time whenever it syncs. About once a day. And it manages to show the same minute as the rest of my clocks. Since I'm not using it to time stamp critical log data or something of the sort I'd say that's just fine.
 
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Mr. Buzzcut said:
A decent quartz watch can be around +- 15 seconds per month so why the obsession with constant NTP or radio updates? It might be fun to talk about but it matters to just about zero people's lives.
.
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I agree with you.
I'd suggest if the Apple Watch can keep it's accuracy to +/- 15 seconds per month.
Or, if we expect Apple does have a higher quality standard than your typical cheap watch, let's say 10 seconds a month, if left to it's own devices, without needing any outside source to correct it, we'd all be pretty happy with that.

Hope someone can one day do some tests for us.
 
So it uses GPS. Sucks up more battery life and lets big brother Apple know where you're at 24/7... or, rather, if the anti-government people get their undies in a knot over purported government surveillance, the same standard should hold true for any groupings of people, no?

Piggie said:
I agree with you.
I'd suggest if the Apple Watch can keep it's accuracy to +/- 15 seconds per month.
Or, if we expect Apple does have a higher quality standard than your typical cheap watch, let's say 10 seconds a month, if left to it's own devices, without needing any outside source to correct it, we'd all be pretty happy with that.

Hope someone can one day do some tests for us.
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Apple borrowed liberally from open source FreeBSD, off the shelf "good enough" Intel and ARM processors, etc, and pushes value on the brand rather than the technology. Apple might sell the appearance of higher quality, but research and fabrication plants cost money. It's good enough to use existing tech.
 
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X--X said:
Apple's Kevin Lynch Explains Method Behind Apple Watch's Precise Timekeeping
hahahahahahahahaha it's a digital watch hahahahahahahaha

marketing at its best
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Of course. Remember, Apple took OS X from FreeBSD. The hardware is off-the-shelf Intel. If people think Apple will make its own precise technology, as opposed to piggybacking off everyone else's... (but in fairness Apple is said to give back to open source as well... pity OS X isn't open source, Windows would vanish in a heartbeat...)
 
rdlink said:
The clock switches over from one day to another and millions of people view it as a reason to waste money and get drunk. Very sad.
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I was thinking one may want to ring in a new year with the person who means the most. If that's Apple watch, that's cool. I'm very fond of my MBA :)
 
X--X said:
Apple's Kevin Lynch Explains Method Behind Apple Watch's Precise Timekeeping
hahahahahahahahaha it's a digital watch hahahahahahahaha

marketing at its best
Click to expand...

Digital watches drift like crazy, its just the way it is. They can have all kinds of electro-mechanical and electronic compensatory mechanisms in them, but not all do.

A great example of an accurate digital watch is the Omega X-33 Speedmaster, which is what the US astronauts get: http://ialreadyhaveawatch.com/watch...aster-professional-x-33/gen-1-and-gen-2-x-33/

It has electronic temperature compensation to cover the range of temperatures seen in SPACE and that's really hard, really, really hard.

https://575717b777ff8d928c6b-704c46...x-33-and-speedmaster_5036f86a_m.jpg?bg=BCAEA2

If you want to see a mechanical clock with mechanical temperature compensation, here's a video. The minute hand moves 2/minute, because the clock "ticks" 2/minute. The clock is not wound at all, and is only powered by temperature variations of the surrounding air:


The clock's "pendulum" is a disc of metal, suspended on a wire. The disc twists back and forth, providing two oscillations per minute, hence the hands move 2/minute. The wire is a special alloy that does not appreciably contract/expand, in the limited temperature range that we call "indoors-shirt sleeves comfortable". The clock will not run well over a real fireplace, and it won't run well directly in the sun in a window situation, but on any normal bookcase/desktop in a normal house, it will run a long time without intervention.
 
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loslosbaby said:
A great example of an accurate digital watch is the Omega X-33 Speedmaster, which is what the US astronauts get: http://ialreadyhaveawatch.com/watch...aster-professional-x-33/gen-1-and-gen-2-x-33/

It has temperature compensation to cover the range of temperatures seen in SPACE and that's really hard, really, really hard.

If you want to see a mechanical clock with temperature compensation, here's a video. The minute hand moves 2/minute, because the clock "ticks" 2/minute. The clock is not wound at all, and is only powered by temperature variations of the surrounding air:
Click to expand...

The meaning of the term "temperature compensation" is very different in the two examples above.
 
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