When a chronograph function is engaged, how is it that the base time-keeping function of the watch is not affected? Does it not add some incremental amount of resistance that could impact the accuracy of time keeping?

Apologies if this has been discussed and I missed it. Also apologies for my ignorance of the topic!

 

Check this thread out: https://omegaforums.net/threads/chronographs-vertical-and-horizontal-coupling.5539/#post-64667

Edit: I do not know for certain that Al addresses your questions in the initial post but it is a good primer nonetheless. I am sure that your question has been answered before, though.

 

How it affects the timekeeping will depends on the specifics of the watch, but in general you can expect on something like a Speedmaster Pro that uses a horizontally coupled chronograph movement, the balance amplitude will drop when the chronograph is engaged. Omega places a limit on how much the drop an be at 40 degrees. That is more of a worst case drop in my view, and typically it isn't that much.

Although that amplitude drop can have an affect on timekeeping, if the watch is set-up well, it won't be a lot. Just for comparison the drop in amplitude from horizontal to vertical positions can be that much, so in the end, it's not usually a significant impact on timekeeping.

Cheers, Al

 

Thanks for the link. I read Al’s post - very interesting. I will need to re-read to make sure I am following but that is a great jumping off point for me to research further.

Al - your response in this thread makes sense. Thanks for the quick reply there. This is fascinating !

Edited to add- how can I determine if my chrono movement is horizontal or vertical coupled? I suppose if I re-read that link and study photos and schematics I can figure it out.