Re: [Leica] M Shutter Speeds

[John Collier <jbcollier@powersurfr.com>]

The last test that PopPhoto did on a M camera all the shutter speeds were
within 10%. That is very good for a mechanical shutter. The M shutter, while
very simple, balances different adjustments to get the desired effect. It is
all too easy for a repair person to just tweak one adjustment to effect a
repair. You can increase the curtain spring tension to make a shutter work
that actually needs cleaning and lubricating and this will effect other
things down the speed range. Or you could just play with slit widths as
well, same problems.  The correct thing to do is to start from the basics
and work up. So clean shutter mechanism first, curtain tension to spec,
adjust curtain brakes, and so on.

Having said all that, it is common for the 1/1000 setting to drift slower
over time. Some repair persons set  the shutter curtain tension slightly
lower and the speed to 1/800 which seems to help. As you can see, M cameras
benefit from being serviced by technicians with a great deal of experience
on them.

I am not a camera repair person as my speciality is British cars and SU
carburettors. The SU carburettor is the simplest mechanism in the world but
it only takes an inexperienced person 30 seconds with a screw driver to make
the engine very poorly indeed.

John Collier

> From: Rick Dahms <shout@nwlink.com>
> 
> I was told by my camera repair shop owner that all the M shutters are
> inaccurate at one end of the spectrum or the other. He said that you need to
> select the "speed area" that you're going to usually shoot around and
> calibrate the speeds for that "zone." And that the shutter speeds will be
> less accurate as you move away from that zone.
> 
> It came up when he was checking my R8s. He said that he wished Leica would
> put the R shutters in the Ms. This guy runs the best shop in Seattle. Is
> this a well known problem? Is it an accurate depiction of the M shutter? He
> says it's the same with the M6. Comments?
>

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