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Comment by jonhester | Hacker News Reader

Mechanical watches, think Rolexes, have smooth second hand movements but they are acutally still ticking, just about 6 times a second. The Apple Watch, on the other hand, has a second hand with 60 ticks per second so that the second hand is about 10 times smoother.

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Some "hi-beat" watches tick 10 times per second (still well below 60). Seiko's Spring Drive (http://en.wikipedia.org/wiki/Spring_Drive) offers continuous movement, but it's not completely mechanical (a quartz oscillator controls the escapement). I would rather have one of these than an Apple Watch: https://www.youtube.com/watch?v=8m-5YpNUwgc

(Edit: only now have I noticed it was already mentioned in another comment)

Correction: Rolexes tick 8 times a second (or 28.800 beats per hour, as is used by watch people). 6 are the vintage ones.

You are wrong. The movement moves at 8 Hz per second, but it actually takes two cycles to actually tick once, so it's actually 4 ticks per second.

The old watches tick at 3 times per second on 6 Hz movements.

No, I'm not. It's 8 ticks per second. I have one and I have checked. Look at this video of the hand up close (it's a 28800 bph movement):

https://www.youtube.com/watch?v=FxgahvNH3q0

I don't know many mechanical watches (especially Rolex) that ticks at 6 times per second. That requires the balance wheel to be beating at 12Hz.

Old Rolex tick 3 times per second on 6 beats/second balance wheel movements, and modern Rolex do 4 ticks per second on 8 beats per second movement.

That's incorrect. The seconds hand moves 6 times in one second on my 7S26 movement (21,600 bph). On a modern Rolex, it would move 8 times in one second. You can check this with a high speed camera (such as the one in the iPhone 6). Nonetheless, there are vastly superior mechanical drives out there that are continuous (Seiko Spring Drive for example).

True as long as there are sufficient number of pixel density to movement of 60 ticks per seconds.

Antialiasing.

And Bulova has the Precisionist line that moves much more smoothly:

> In 2010, Bulova introduced the Precisionist, a new type of quartz watch with ultra-high frequency (262.144 kHz) which is claimed to be accurate to +/- 10 seconds a year and has a smooth sweeping second hand rather than one that jumps each second.

Huh. Cool. I always wondered why they didn't make quartz second hands jump in smaller amounts. Something difficult or not efficient to achieve, I guess.

By the way, Seiko has had a movement for some time that is rated to +/- 5 seconds a year. I think it was on a special edition of the Grand Seiko line (already rated to around 10 seconds a year, so you'd get 5 seconds off less. Yay!)

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