I thot I share this lesson I learned the hard way!
This has to do with labelling 35mm film cassettes (which I do when loading up bulk film into used film cassettes) and using them in cameras with a film window in the camera back that shows the film type loaded.
I have a habit of labelling my film cassettes very close to the lip of the cassette on the side that shows the film infomation for the film window. For labelling, I use a printed piece paper (normal 80gm) and taped it onto the cassette (at the location described above) using 3M tape (the normal transparent kind available in stationary stores). As the label is relatively large, I use overlapping pieces of tape to make sure it sticks properly and so that the processing lab would not make a mistake on identifying it wrongly wen developing.
My action above somehow causes the light trap around the film window on the camera back not to seal the ambient light properly when the back is closed. This causes orange streaks to appear on every frame of the roll. The way in which the taping is done also modifies the streaking pattern a little.
I had suspected both the processing lab and the cameras I was using for this problem, until I developed 20+ rolls from a trip that showed the problem . To confirm that my hypotheis was correct, I shot a bulk rolled cassette with the label moved to the rear and another "off the shelf" roll using the same camera and process at the same lab. For the bulk rolled one half was exposed with the film window "opened" and the other half with the windows covered by a piece of black tape. Both rolls came back from processing *WITHOUT* streaking.
So label your 35mm film cassette in the right place! I'm going to be labelling them over the DX code area the next reel of 100' film I buy.
Hope this helps somebody out there; if you have "been there, done that", well just enjoy a small laugh at my expense
chgoh @ 12:37 pm, 8 December 2004