film damage cause question

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I have looked around on the internet and cannot find this problem accurately described, but some 400 speed film which travelled (lead bagged) through a number of x-ray machines has a horizontal, dark grey stripe (not straight but nearly so, not much variance in width) across most of the roll. Is this consistent with x-ray damage or some other sort of problem/defect? Assuming

A number of 100 and 64 speed rolls which travelled with this one had no visible marking; as soon as I get back I am going to test some unused 400 speed rolls that travelled in this same bag but were not used.

Any ideas on this will be appreciated, if need be I will have a couple of frames scanned and put them up.

thanks

randall

-- Randall Thomas (Dogfooddog@aol.com), March 30, 2002

Answers

A few surmises. Faster film is more sensitive to damage from x-rays. There may also be some sort of uniform variation in the thickness of the bag's shielding. That the slower film(shot in the same camera, I assume)showed no such damage would rule out light leaks.

-- Gary Watson (cg.watson@sympatico.ca), March 31, 2002.

Randall: Was the film in question in the camera when it went through the x- ray? I had a roll damaged under peculiar conditions. The roll had been in the camera for a while, and I presume abrasion from the idler roller on the take-up side caused the damage. It was a vertical line from one side to the other of a semi-uniform width of about 3-7mm wide and a little ragged. ??

-- Mark A. Johnson (logical1@catholic.org), March 31, 2002.

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