light leak?

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getting odd rectangular patches on a few negs taken with my M6. they look like very slight light leaks, just a darker section on the neg and occur just now and again. they are on the right hand side of the neg, about a quarter of the way down. I suspect shutter bounce or something. any ideas?

-- brian (briandavidstevens@excite.com), September 26, 2001

Answers

I have had this happen on my M3 from time to time, almost always on a negative right after I changed lenses outside in bright sun and wasn't careful about aiming the open camera body away from the brightness. The shutter curtains are as light tight as any cloth curain on an SLR, but the Leica M does have a mirror to deflect the light when changing lenses.

-- Andrew Schank (aschank@flash.net), September 26, 2001.

I second Andrew's suggestion - this happens when the lens is off and the mouth of the camera faces into sunlight. Sometimes the patch runs the full length of the negative; sometime, as in your case, most of the curtain is tight (or the sun is hitting only one end of the shutter box) and the patch is only on one side or another.

The reason the patch doesn't start right at the edge is that the shutter curtain travels in a slot, and the light has to get down into the slot at an angle and bounce off the metal bottom of the slot to get around the curtain, so that it is a very grazing light by the time it reflects back to the film (actually traveling UP from the bottom of the camera instead of straight-in from the front), and the wall of the slot on the film side of the shutter curtain acts as a shade, protecting the first 4mm or so of film.

It take a very bright light (the sun) hitting the shutter at just the right angle to cause this, but it's something to always keep in mind when changing lenses - but I still managed to do it myself on a couple of frames this past weekend (Velvia, no less!).

-- Andy Piper (apidens@denver.infi.net), September 26, 2001.


I second what the other guys have said. There are limits, however, and if this is a frequent thing, you should probably send the camera off to Sherry and have her check/replace the light baffles in it.

-- Tom Bryant (boffin@gis.net), September 26, 2001.

thanks chaps!

-- brian (briandavidstevens@excite.com), September 27, 2001.

Is this a common fault? I see this on my M2, just as Andrew & Andy described. Is it expensive to rectify?

thanks

-- Jeremy Lewis (jeremyb.lewis@gbr.xerox.com), November 22, 2001.



Jeremy: The cheapest fix is just to be aware of it and protect the camera body from direct sunlight when changing lenses - just turn away from the sun for the moment when no lens is on the body, and get the new lens on without delay.

If you're still getting leaks, then something may need adjusting. Never having had a repair myself I'm not sure of the cost - CLA's (clean/ lubricate/adjust) mentioned here have been quoted in a wide range either side of $250. If the shutter curtains actually need replacing, that runs higher - hopefully someone else reads the "Recent Answers" and will jump in to tell us just how much.

-- Andy Piper (apidens@denver.infi.net), November 22, 2001.


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