Shutter curtain problem?

[pierre_boucher]

<p>Hi to all,<br /> Looks like a part of the let half is overexposed. Shot with a M645 1000s, 80mm/2.8, Ektar 100, steady shutter speed of 1/125 for all 15 frames. The only pic like that out of 15. Temperature : ±0 C.<br>

Thanks</p>

<p> </p><div></div>

[jim_momary]

<p>Your camera was made between 1976 and 1990, hence anywhere from 35 to 21 years old.<br>

Have you ever had it CLA'd to ensure the shutter operates smoothly, espcially at lower lube-congealing temperatures?</p>

<p>Since there is an electromagnetic moving coil shutter control involved here too, the battery condition (which declines with temperature) may also be part of the picture.</p>

<p>The user manual on page 57 talks to this (somewhat) and a camera storage temp of 15 - 100 degrees F is mentioned, but nothing about operating temperature. They do mention, keeping the camera out in the cold ONLY for the time to take the shot.</p>

<p>Jim</p>

[marc_batters]

<p>Only one pic out of 15 shows this? Was it the last or first frame? Just this roll, or is it ongoing? <br>

It could be from fogging; allowing the paper backing or film to unwind during loading/unloading.<br>

I see a fairly sharp boundary line though, not usually the result from fogging. As suggested - CLA.</p>

[rodeo_joe1]

<p>Absolutely nothing to do with the battery! The shutter is electronically timed, but is essentially a simple mechanical shutter. If the shutter is sticking (which it looks as if it might be) then it needs a mechanical adjustment. The shutter in <em>all </em>M645 series cameras is driven by a tensioned spring, and the rather crude electronics simply time the interval between the first and second curtains of the Focal Plane shutter. The only connection between the mechanical shutter and the electronics is via a single solenoid, which releases the second curtain when the exposure time has passed. This solenoid cannot possibly arrest either of the shutter curtains part way through their travel.</p>

<p>Anyhow. The change in exposure could also be due to fogging, and it looks more like fogging to me, since the contrast appears to be lower in the lighter part of the image. The clue would be the appearance of the film margin, and unfortunately the OP hasn't shown the relevent part of the film edge.</p>

<p>Pierre, if the fogging extends across the unexposed edges of the film, then it's fogging caused by loosely wound film. If the fogging stops at the edge of the frame, then you might have a problem with a sticky shutter.</p>