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M6 Shutter bInnacuracyb vs M7 Electronic Shutter


Well-Known Member
Hi --

Just about to invest in first Leica gear, after long SLR usage (will be keeping SLR for different kinds of work not suited to rangefinder).

I have several friends with Leicas and been fortunate enough to use an M6 recently, hence falling in love with a Leica.

I've been doing research, naturally, about which is the best Leica for me. The M6, or later, sounds about right, but I'm trying to decide whether to spend more on an M7 NOT because of Auto Exposure (like to work manual, although aperture priority is good too), but because I've read a few worrying posts on various forums about alleged innacuracies of the M6 mechanical shutter (usually at least 1/3 stop out?).

The M7, of course, has a highly accurate electronic control for the shutter...

But, how much difference does anyone notice in practice? Are all you M6 users out there having genuine problems with exposure due to innacurate shutter mechanisms?

It seems almost mad, superficially, to me that a camera as optically fine and well built as a Leica should have such an innacurate shutter - how much truth is there to this? The second hand price difference here between a good used M6 and a good used M7 is about £500... I could buy another, or much better Leica lens to go with the M6, or buy an M7 with more 'accurate' shutter...

Any insight appreciated!

I've been using the Leica M6 since it came into being built in Solms. I've never had a shutter problem (or any other for that matter). The M7 is Leica's first foray into an electronic shutter in the M series. The R3 was their first electronic shutter in that series. No longer fixable! (Copal doesn't make the shutter anymore).I don't know about R4 to R7 shutters. Were they the same as R3? Who makes the shutter mechanism for the M7? Is it Leica, or is it made by a third party for Leica? (Like the CLS in the R3--Copal Leitz Shutter). Leica's experience with cloth mechanical shutters is as old as the cameras themselves. My vote is for the M6
I have never had a problem with any of my Leica M6s or the M7. The classic is now over 20 years old.
Colin and Elliot - I should clarify, that the reports I have read were not discussing shutter 'problems' with the M6, or other mechanical Leica shutters, but rather that even a properly adjusted Leica mechanical shutter's timing is likely only to be accurate to +/- 1/3 stop due to mechanical tolerances - unlike electronic shutter timing which should be dead on every time, thereby removing one of the variables in getting accurate exposure. However, if this theoretical position isn't making much difference to working M6 photograpers (i.e. If you're all taking well-exposed photos even on slide film, etc most of the time) then its all academic and I may as well get an M6... Elliot - since you have an M6 and an M7, have you actually noticed a difference in exposure accuracy between the two? If I don't need to worry about this as a buying consideration, I'd much rather spend the extra money on a good lens for an M6 setup. Thanks again, James
James, To start with, NO electronic shutter is going to be "dead on" everytime. Every shutter be it mechanical or electronic is built to tolerances. If you buy an M7 unless you blindly follow the manufacturer's ISO, you will conduct your own tests. If you buy an M6, you will/should do the same.
I shoot Vevia 50 and previously Kodachrome 25. I've never had exposure problems because of incorrect shutter speeds. I think it's all academic. What is important is that if your 1/125th is 1/100th, or your 1/500th is 1/600th that it is always so. I have shot with both mech. M's and elec. R's and have noticed no difference in exposure accuracy even with 25 ISO transpareny emulsion. Save your money and buy that extra lens to put onto an M6
It is my view that the reason one chooses the M7 over the M6, is to gain the advantage of the AE.
This helps to take opportunity and candid shots quickly, and to deal in places where the light is forever in flux.
The fact that the shutter exposure is indeed more accurate is of secondary importance (clock-precision).
Nonetheless, exposure accuracy is a plus for slide films, but you still have to judge what you are using as the reference point.
I wouldn't worry about the longevity part, ..these days electronic parts are very good, ..at least for 20 years.
Hi Jim:

You know, I have never given the shutter speed accuracy even a passing thought. When there is an exposure error it is completely mine. I have never noted any "exposure accuracy differences ( sic )" between any of the M6s I have had, the M7, or the MP.

Good luck with your choice, and let us know how you are doing with your new lens!.

Colin, You're absolutely right, that's excellent advice, as long as the shutter speed is consistent it won't matter if its off by a fraction of a stop IF I carry out shooting tests and adjust accordingly. I suppose one should do this if the camera is serviced also, as I presume shutter tolerances may be adjusted at that time? Thanks for the advice! James
Hi Elliot

Thanks for the clarification on that point. Its especially useful that you've used all the models of Leica I'm considering and haven't noticed any difference in practice regarding exposure accuracy on the part of the camera. I'll definitely be buying a nice M6, with either a couple of summicrons or possibly one good summilux... Now, whether to go M6, or M6 TTL...

James --

"Imagination is more important than knowledge" -A. Einstein
William --

You guys are doing a fairly good job of convincing me not to worry about paying extra for an M7 on the grounds of exposure accuracy. Thanks for the advice.