Monday, September 28, 2015

How Important is Accuracy in a Watch?

When you think about your watch’s accuracy—or inaccuracy—consider this opening page from F. Paul Wilson’s spooky and brilliant novel, Nightworld:
On May 17, the sun rose late.
Nick Quinn heard the first vague rumors of a delayed sunrise while filling his coffee mug from the urn in the lounge of Columbia University’s physics department. He didn’t pay them much mind. A screwed-up calculation, a missed observation, a malfunctioning clock. Human error. Had to be. Old Sol never missed appointments. It simply didn’t happen...
“What’s all this I hear about the sun being late? How’s a story like that get started?”
“Because it’s true....Sunrise was scheduled at five twenty-one this morning. It rose at five twenty-six. Five minutes and eight-point-two-two seconds late.”
“Come on, guys. We set our clocks by the sun, not vice versa. If the clock says that the sun is late, then the clock needs to be reset.”
“Atomic clocks, Nick?”
“Then the clocks are wrong!”
“Atomic clocks? All of them? All experiencing precisely the same level of change in nuclear decay at the same time? I doubt it. No, Nick. The sun rose late this morning.”

If Nick was a watch collector, he might be pleased that it was the world that was broken, rather than his watch.

Bulova Ultra High Frequency
watch, also ultra accurate.
Photo from Bulova.
If you want an accurate watch, a watch more accurate than Galileo could ever have imagined, it can be had for about as much as you’d pay for a few beers and burgers at a sports bar. These watches receive a radio signal from a radio station whose signal is itself coordinated with an atomic clock. Rado makes some stylish radio-controlled watches, and Casio makes some that fall into the beer-and-burger price range. While these radio-controlled watches are quartz watches—which themselves are only as accurate as their quartz crystal, which is to say pretty accurate because they are synchronized every day with a very, very, very accurate clock—they are reliably accurate to within a second a day.

You can also buy a watch whose time signal is synced with a GPS, which is accurate to within 40 to 80 nanoseconds. Because radio signals travel only as fast as the speed of light, there’s going to be a little delay between when the signal is sent and when your watch reads it. Seiko’s Astron is one of these GPS-controlled watches.

Or you could get a Grand Seiko 9F quartz with a movement that doesn’t rely on a radio signal. Grand Seiko quartz watches are accurate to within 10 seconds a year. Bulova’s ultra high frequency watches are also accurate to within a few seconds a year.

So, great. You can have a super-accurate watch strapped to your wrist, a watch that would make the Apollo astronauts envious.

But why? There’s no watch complication or feature that anyone needs—moonphase, date, alarm, perpetual calendar, minute repeater, for example—other than the hour and minutes. (Some watches, called slow watches, dispense with the minute hand entirely, and just have an hour hand.) I’d throw accuracy into that mix of unnecessary complications. We just don’t need super-accurate watches. (Unless you’re in the military, where timing matters.)

Of course, cell phones have accurate clocks right there on the front screen, so if accuracy is for some oddball reason required, an accurate clock is no further away than our pockets. But let’s put our cell phones aside for a moment (always a good thing to do anyway), and ask, “Under what circumstances do we need to know the precise time to within a few seconds, or even a minute?”

Not when you have a flight to catch. You’re going to get to the airport early anyway.

Not when you’re meeting a friend for dinner at a restaurant, because even if you have an accurate watch, there will be uncontrollable obstacles to being exactly on time, such as traffic delays, connecting train schedules, whether you’re walking slowly because it’s so damn hot and humid.

Not when you’re running late for a meeting. If you’re already late, being another 30 seconds late isn’t going to make things any worse.

Not when you’re taking an exam, because that last minute isn’t going to do you any good anyway.

Not when you’re wondering when the actual movie will begin because nobody knows how long the movie trailers will go on for. (Hint: a long time.)

Unless what you’re doing itself involves something that’s on a precise schedule, you’re fine if your watch is off by a minute or even a few. I live in Tokyo and the trains here are always on time, so when the schedule says that your train is going to leave at 5:08, it’s going to leave at 5:08. Tokyo and other places that have advanced, reliable and accurate train systems may be the only environments where equally accurate watches are a good idea. But even in Tokyo, a watch with a regular ole ETA movement gets me to my trains on time.

Still, accuracy is nice to have. An accurate watch is an emblem of great engineering. An accurate watch shows how we can keep improving on something that’s already great. An accurate watch is like a reliable best friend. An accurate watch is, like your jumping second hand or any watch complication, fun. And fun is as good a reason as any to wear a watch.

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