[Leica] Technical Problem from Film Era--can anyone help?

[jshulman at judgecrater.com (Jim Shulman)]

While I really love shooting with my Mamiya M645, I?ve noticed with the
last few rolls that I?m getting what looks like a light streak

http://gallery.leica-users.org/v/focusit/band+of+light+problem.jpg.html

On perhaps one or two frames per roll.



What is the cause of this?

?       Shutter problem (though why would it extend to the edges of the
frame)?

?       Light leak in the camera? (could be, since the foam?s older than
half of the US electorate)

?       Mistake with loading the film onto the reel (I noted that the film
tangled a bit while I loaded it this time.  The blotches at the left of the
frame may have been caused by the little friction balls in the plastic reel
used to cinch the film along.  While I sometimes see those on 120 frames, I
never see them in 35mm, since the cinching takes place along the
performated area.  Guess it?s time to find someone with surplus 120 Hewes
reels and a tank!)



Any help would be greatly appreciated!



Thanks,

Jim