Leica IIIF Shutter Issue?

billyryanwill

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Hey everyone,

New here, but need some advice on recent roll of film I've had back as it's kind of stumped me.

I have ended up with pretty much two whole rolls of half frame shots back from the lab.

I would have automatically assumed that these would be caused by a shutter issue, however I have also had another couple of rolls which I've developed myself which did not have these issues. So I'm left with two theories:
- There is a shutter issue (which means it's CLA time).
- The extra long lead has caused an issue for the development.

I've attached a few shots from the rolls in question, plus one that I developed at home myself.

All the shots were taken between 1/60th and 1/1000th. The colour shots were done by the lab, the B&W ones at home.

fujig645-200215.jpg

fujig645-200230.jpg

fujig645-200240.jpg

fujig645-3200026.jpg

fujig645-3200029.jpg


Any similar experiences? I've looked at the shutter curtain and done some slow mo video of the shutter and it doesn't look to the untrained eye to be an issue.
 
Welcome to the forum !

It looks like the shutter is capping, ie: the slit formed by the two shutter curtains is closing up too soon as a result of one curtain running too fast or too slow.

Shutter curtain bounce is usually a darkness or double faint image at the end of the film frame, so I don't think that is the case here.
 
Thanks!

Is this easily fixable through CLA?

Yes it is.

You might be able to ameliorate the problem with tensioning or slacking the offending shutter curtain, but that is a slippery slope, as you have to be sure the shutter capping is the real problem and not mechanical interference of a curtain or a loose curtain tape.

You also need to measure curtain running time, hard to to on cameras that have no open back, so a pro CLA is the best way to go, worth it for a valuable camera like a IIIf and needed on a 65 year old camera, if you plan to use it.
 
Welcome to Rangefinder Forum.
It's of much help to know which frames were shot at which speeds. If a focal plane shutter such as used in the Leica screw mounts needs servicing it will often be the fastest speeds and/or the slow speeds which will be most affected. Slow speeds because the escapement may benefit from cleaning, the fast speeds because the higher the speeds are the tighter the slit width needed becomes, and the tighter this becomes the less tolerance exists for even minute variations in curtain travel of a millimetre or so.

Looking at the colour roll it seems the full frame has not received exposure. Unless you possibly have been inadvertently fouling the shutter speed dial with a finger it is hard to envisage any other cause than an irregular shutter which, if the camera has not been serviced for some years is not at all unlikely. I don't see how a lab could develop a portion of certain negative frames adequately without also achieving identical development of the remainder.

I would therefore suggest that the most badly affected frames were likely those exposed at 1/1000 to perhaps 1/250, certainly 1/1000 or 1/500 as it seems the shutter is capping early in some cases. It is entirely feasible for a IIIf in need of service to produce satisfactory exposures at 1/60 but not at its fastest times.

If you would like to be definitive load a short roll of film (black and white is fine or even preferable, given you can control the entire process) and take a series of equivalent exposures at speeds from 1/1000 down. Ie different shutter speeds and adjusting aperture to maintain same exposure value. A landscape with plenty of cloudless evenly lit sky is ideal, but a well illuminated light coloured wall or building that is evenly lit will also work. Obviously you will need to note the exact exposure settings for each frame. On developing the roll examination of the various frames will inform what the shutter is doing at each speed. If you post these we can help assess them.

With most cameras a decent shutter tester will reveal any shutter problems quickly and easily without the need for a test roll, unfortunately with the IIIf film gate being inaccessible to most tester sensor probes, the old fashioned method is usually the easiest unless one is prepared to remove the mechanism from the body casing.
Cheers
Brett
 
Hey Brett,

Thanks for that. From memory and my notes I believe that the majority of my shots were between 1/250 and 1/1000 for sure (it was pretty sunny).

The one full frame on the roll was definitely shot at 1/60 as the light had gone by the time I'd taken it.

I'm glad you suggested that as a plan because it's something I'd presumed I'd need to do. I'll take a test roll out with me tomorrow to test out.

My only confusion is that my previous rolls had worked (for the most part) fine, so it seems that potentially it has only recently become an issue.

Thanks again,

Billy
 
Excellent advice given above. Make the short roll long enough so that you go through all the shutterspeeds. But I agree on the CLA, especially if it is intermittent (worked earlier but not now) that can drive any decent person nuts.
 
While you are in there, before loading the test roll, cross your fingers and check for film chips that could be fouling the curtain travel path.
 
On the very first shot, I think it is not only capping but I believe some bounce is evident at the extreme right edge.
 
And when you figure it out and have a CLA hope you don't get this on the first roll back: someone said it was shutter bounce??

Kodak 400 Max expired by John Carter, on Flickr

So be careful who you use for a CLA.
John,
that is the first curtain rebounding into the edge of the film gate. It's a great example of what it looks like. You can see the basic exposure is consistent right across the film gate, the relationship between the two curtains looks good. But, when the first curtain has ended its run, the edge has rebounded back into the film gate over a few milliseconds, and that strip has not received the full exposure that the majority of the negative got.

It can be caused by curtains that have been over tensioned to compensate for a dirty or worn mechanism instead of getting it back to an acceptable condition. I'm not suggesting the person who worked on your camera did this. The fix could be as simple as adjusting the curtain brake which is meant to prevent the curtains rebounding when they have been set to the correct running speed.

The shorter the exposure time is, the greater a percentage of the nominal exposure this bounce event will be and hence, the easier it becomes to notice. By the time you have dropped the shutter speed to, say, 1/60 or even 1/125, whilst the bounce will still be happening, in most shutters that use the same curtain travel speed at all times, as a percentage of the nominal exposure time the bounce reduction in exposure is so insignificant that its effects are not usually visible.
Cheers,
Brett
 
Brett, thanks for that. I've had my IIIf CLA'd so many times I'm just not for up for another war. This is/was at 1/100 and I only notice it at that speed so I'll live with it for a while.
 
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