How much does power reserve and accuracy matter to you?

I rotate watches almost every day, could care less tbh.

Unless I'm honeymooning with a new watch in my collection, I almost always wear a different one each day. Power reserve doesn't really matter to me all that much, nor does accuracy as long as the watch is functioning properly.

Accuracy yes, power reserve I don't care.

That's what I thought, until I found a watch that was just always running and on time.

I think this question can be broken down in two follow-up questions: “What is the market position for the watch?” and “Is it manual-wind or automatic?”.

The relevance longer power reserves in self-winding mechanical watches in term of convenience depends on one’s watch-wearing habits. For a market who has not lived and breathed mechanical watches, it’s probably a good thing so that a person doesn’t get frustrated with it. Plenty of people buy winders but still.

For accuracy, i think under $500 retail okay accuracy is fine, but over that having good accuracy should be part of the package. It doesn’t have to chronometer-level, but it should be pretty good, because $500 is a lot of money to ask of a consumer. At US $1 000 and up chronometer-like accruacy should be common practice. That’s the price of luxury product that is a for-life purchase.

Also depends on your interests. I got my wife a nice watch and she was surprised that it stopped if she didn't wear it for a few days, (it's a moon phase, so not easy to set, but needs to be running long term to be useful). I bought her a winder, then she was not impressed the time was off after a month.

She is happier with her next watch: Cartier Tank Quartz. It has quartz on the inside and diamonds on the outside... Not my kind of watch, but it makes her happy though.

edit: She is vegetarian on Full and New Moon, so the moon phase is more than just ornamental.

Define accuracy.

A 24 hour day consists of 86,400 seconds. Is 99% accuracy acceptible for a mechanical device?

a 99% accurate watch will cause you to miss the train in Italy

99.9% you might miss the train in Japan

(1% will lose you 14 minutes a day for those who don't want to do the math)

I'd define accurate is better than 50 parts per million (ppm), or about 5 seconds/day. That's chronometer level, right?

I started my interest in vintage watches, so I never really cared about these things. But the SLGA007 Minamo changed my view completely.

With its 5+ days reserve, and <1 sec/day accuracy, its often the only watch running, and I’ve found it has become my go to watch.

😆

Definitely.

You could get her a Tissort Carson Moonphase. That’s quartz

I’m German, I cannot give you one answer to two questions. 🙃

It annoys me that every high end watch I’ve had is not very accurate compared to my lower end stuff like Tudor/Sinn/GS.

I get why, I guess.

My metric is Reserve (hours)/Accuracy (sec/day)

So Minamo 9RA2 0.5 sec/day with 120hr reserve = 240hr-day/sec

Rolex GMT 3285 is 2 sec/day with 72hr reserve = 36hr-day/sec

Various Miyota 9015 ~20sec/day and 42hr reserve = 2hr-day/sec

I tend to wear a watch for several days in a row, so I prefer if it's not more than like 10 or so seconds off per day. I also regularly slip in a g shock for a half or full day when I'm doing something especially hard on watches, so it is nice when my watch can be taken off for a day and make it to the next day before it dies. Fortunately, that's only about 32 hours for a day and two nights, so it's a relatively low bar if my automatic watch is actually wound. I might shake it around a bit to make sure it lasts, but that's not a big deal.

If I want accurate time keeping and extended operation time, I'd get quartz. Mechanical is only an indulgence to me

Accuracy and power reserve aren't things I really take into consideration when buying a watch. They are both very nice things to have, and I do appreciate them when I have them. My SLGA009 White Birch is almost always running because of the 5 day power reserve, and the fact that it gains 2 seconds a month means I can always trust it to be accurate. Most of my other watches won't run that long so accuracy becomes much less imprtant, as I'm most likely setting it when I wear it anyways.

On a balance spring watch, accuracy is affected by power and so can be related to power reserve depending on usage. This isn’t true with spring drive. My spring drive watches maintain their accuracy up until the moment they stop. Further, my daily logging of springdrive accuracy over many weeks leads me to believe their accuracy has more to do with set factory regulation tolerance than anything else…I.e their gain per day is consistent and predictable. My 9RA6 is a consistent +1.8 sec per month, and my 5R65 is a consistent +5.4 sec per month. I’m intrigued by the gold rotor badged spring drives which are supposedly maunually and individually regulated at the factory. Would love to hear some user timings on those.

Not much

I rotate every week, so both accuracy and reserve would be wasted on me.

PR and accuracy aren't deal breakers. I rotate watches enougj that it doesn't matter and it's nice winding and setting them when they do stop. I've also learned PR to me matters more than accuracy/beat rate

Power reserve is way down on trhe priority list but preccission/accurascy is at the top for most watches. I mean like a Meistersinger isn't all that precise, how can it with only one hand, but is still a desireable watch brand.

Accuracy, extremely important — I wear my mechanical watches as dailies and time my life/work by them. 3-day power reserve is a VERY nice to have, but not necessary…especially if you regularly wear just the one watch. For me, COSC is a minimum, Superlative preferred, especially if I’m dropping more than a couple of hundred on a watch.

Having both is a convenience that’s definitely missed once you’ve experienced it (the past month I’ve been rotating between my Luminor and Explorer II and not had to wind or set the watches once, even when I’d leave either sitting for the weekend (granted the Luminor isn’t as accurate as the Explorer II, which is still running at close to 0spd a few weeks in).

Similar experience, thats why I have come to appreciate my SLGA007. PR and accuracy do have to work together. A long reserve on an inaccurate watch is not so useful

After almost two decades of being a C I got tired of serving the watch, deserted to the A side and bought a Quartz watch.

Yep. There is a side of me that thinks it is absurd for me to tell the watch what time it is instead of the other way around.

The higher end Spring Drive are sort of best of both worlds.

If you know the accuracy on the Spring Drive, then you are my kind of guy! How do you get the 0.1s tolerance precision on error?

My 9RA2 has been +1 sec per month.

Hmm, I am realizing that a video of the hand motion vs atomic clock might work well...

For me the astounding accuracy and elegance in design of a mechanical piece is part of the attraction.

I would prefer a 1968 Jag E-Type convertible over a 2024 Electric Ford, despite the Jag being less efficient, slower, lower capacity, less reliable, louder, smellier, less waterproof, and more expensive to service.

Make it a 2025 Tesla Roadster... and I am not sure which one I want.

Accuracy on mechanical is possible and in equal part impressive for sure, but quartz will still have it beat in that regard. I don't think the combustion engine vs electric vehicle comparison is comparable because EVs don't really solve all the problems the former has but introduces new ones.

I get you though, I'm not trying to be dismissive of mechanical watches. I do like them but wear them for different occasions than everyday

I use an app called “Watchtimes” which is designed just for this application. Unfortunately it doesn’t use the camera to but rather it depends on a user pressing a button when the watch is at particular time, and then records the offset from atomic. I think this is fine for typical mechanicals, but it’s pain for spring drive, because it does require one to be at the top of their game. I use bright light and a mangified view, and still there is plenty of human error that averages out over many samplings. Here are some screen shots from my two springdrive. You can’t see all of the data points as they scroll off the bottom. The 9RA6 (SLGA015) is over a month of daily logs, and my 5R65 ( SBDB013) over two weeks.

You can see the slope is quite consistent. The small fluctuation I attribute to human recording error since these times verge near human limits (or at least mine). The straight slope suggests to me spring drives are capable of far greater precision if they are regulated.

This made me smile — I love the way you broke this down my man (love data). Like you, I didn’t give much thought to the accuracy + PR combo until I actually owned a watch that offered both (my dual-barreled Planet Ocean 42mm 8500), and now that combo is an extremely nice-to-have, with Chronometer at a minimum for any watch I consider a daily. Chronometer is -4/+6 and those I’ve owned in the past have been all over the place within those limits. Grand Seiko Hi-Beat is -3/+5 over 3 days, never owned one but have always been tempted by the Shosho (tangentially, I also prefer Hi-Beat and traditional mechanicals to Spring Drive personally). METAS is 0/+6 over 55 hours and most of mine consistently run within +1 with the accuracy approaching the limit as the reserve winds down. Superlative is -2/+2 over 70 hours, most of mine run at close to 0 with the accuracy hitting the limit as the PR winds down.