[Leica] Interesting technical problem--your thoughts?

[jshulman at judgecrater.com (Jim Shulman)]

Well, I've been shooting with my IIIb/SCNOO ensemble for a few weeks, and
love it.



With one exception:



The other day I was merrily shooting away with Kodak 5222 loaded into
several of the Leica metal FILCA cartridges for the IIIb/SCNOO
combination.  After processing, I noticed that several of the frames seemed
to have a strange fogging, almost like a crescent dagger from the bottom of
the frame (bottom, as in what was in the bottom of the camera) about every
so often, maybe five frames total out of 40.  These came when I was
shooting in regular daylight--some bright sun, some shade, and did my film
loading in subdued light (or indoors).  I've attached an image file showing
the offending "dagger" fogging.

http://gallery.leica-users.org/v/focusit/filca+fog.jpg.html





Seemed strange.  So I ran a side-by-side test at end of day, first shooting
a roll of FILCA-loaded Kodak 5222, then a roll of Fuji Acros 100 in the
standard Fuji metal cartridge.  Both came out fine with no dagger-like
fogging.  The sun was out, but not brightly.



I thought I might have misloaded the FILCAs for some reason, so I loaded
another and went out shooting in regular bright daylight.  Again, every so
often there was the dagger-like fog at the bottom of the occasional frame
(and no pattern to the "daggers"; they appeared irregularly.)



Yesterday, I ran another test: I shot a roll of very old Plus-X, in the
standard Kodak cartridge, in bright sunlight.  I took off the lens and
aimed the camera at the bright sun; I shot in brightly lit areas, I shot in
dim areas.  No fogging whatsoever on the film.



Any idea what's happening?  If it were a camera light leak, it would have
happened on all types of film cartridges, both standard and Leica FILCA.
If it were a FILCA problem alone, it would have leaked when I shot toward
the end of day (in the double-blind test).  If it were a darkroom loading
problem, it would have happened to all my film.



One suggestion I've received is that there's a tiny light leak near the
take-up spool, based on the sharp definition of the leak pattern.  If
that's the case, though, why not on both FILCA and non-FILCA loads?  After
all, the take up spool has nothing to do with the type of film cartridge.



As the King said, "It is a puzzlement".



Thanks,

Jim Shulman

Wynnewood, PA