Strange pattern in exposure. Light leak?

[andrew_clark1]

<p>Here are three photos from my M4. At the top of the frame on the first two photos and on the left of the third photo, there appears to be uneven exposure. The second problem, seen in the second and third image, is a white crescent in the middle of the image. Both appeared before and after a CLA by Youxin. They are not consistent either. Maybe once every third roll or sometimes 2-3 times a roll. The first two were 250@f8 and the third was 1000, but I can't remember the f-stop. On another roll, which is not included here, I shot the entire roll at 250 @ f8 and the problems only showed up in one frame. <br /> <br /> Has anyone seen this before or anything like it?<br>

http://daytonadesign.com/problem1.jpg<br>

http://daytonadesign.com/problem2.jpg<br>

http://daytonadesign.com/problem3.jpg</p>

<p> </p>

[bob_sunley]

<p>Try making a couple of "dark frames". Advance the film, move the camera around in bright sunlight for 15 minutes, no lenscap on it and the aperture wide open. then cap the lens and fire the shutter. Now advance the film, fire the shutter again. Do not advance the film. Remove the cap and let lots of sun shine on the camera. This will test both shutter curtains for light leaks.</p>

[richard_ilomaki7]

<p>You don't say if you processed the film yourself.<br>

Half moons or crescents are often caused by pinching or crimping the film when loading onto a reel.<br>

Cheers</p>

[alex_lofquist]

<p>They look like pressure marks.</p>

[andrew_clark1]

<p>I do not process it myself. I thought they were from the lab too, until I changed labs and now go to Duggal in NYC.</p>

[canfred]

<p>Andrew I do not see any light leak Alex is right. Just in case you are not aware do not ever expose your camera to the sun without cap, the result would be damage to the curtains foe sure.</p>

[andrew_clark1]

<p>It's definitely not a lens cap issue. I have been on the brightest of beaches without a cap and only one frame of 36 had the issue. I have not used a cap for the better part of 3 yrs and have only seen the issue on 10-12 frames. I found another user that had the same issue with an M6 and it took Leica of NJ three tries to fix it. I also stuck a halogen flash light in the lens mount, inside a dark room, and there was no light leaking anywhere. I think I'll be giving it to Sherry or Leica of NJ this summer.</p>