Posted by DiverD on February 06, 2005 at 12:53:36:
In Reply to: Scanning issue posted by Elaine on February 04, 2005 at 15:50:22:
The rolls do vary. Emulsion is a alive, that is why it must be frozen to be preserved. Each alley-way that coats film produces a slightly different batch of emulsion. There is enough variance to cause the manufacturers to keep track of and label the alley-ways each film batch was coated in.
Scanners need to find a new black and white point with each scan they make, even with rolls of the same film. To start, try setting the black point to the black portion of exposed film that frames the slide, not in the image itself. this will start you out with that particular slide and film's maximum density, you can work from there.