We all know black and white film is very flexible stuff and we can
greatly manipulate densities by using different developers, agitation,
length of development etc. However, this makes black and white film
particularly difficult to scan as what is on it varies so much from
film to film, shot to shot.
Typically when scanning negative film, a
profile is used which shifts the scan toward the best results with the
particular colour response of that type of film. However, long
experience has taught us that this does not work very will with black
and white film - too often the profile makes decisions about D-Max and
D-Min that are not appropriate, and so the final scan does not have all
the detail it should have.
The solution to this
problem is to scan the images using the full dynamic range of the
scanner, as RGB colour positives. This results in a scan with all the
detail from the original film on it. We then invert the image in
Photoshop and remove the slight remaining colour cast that results from
the film base not being perfectly neutral. The final result is a
neutral scan with all the detail from the original film.
The
final result is details rich scans from almost any black and white film
that is exposed and developed within reasonable limits. If you've
cooked your film (ie. over developed) or your film is very thin (under
exposed, under developed) then your scans will reflect this, but the
Imacon can get a good workable result from almost any piece of film. You should expect a result that is significantly flatter (and thus more flexible) than what many typical labs will produce. You will need to apply a contrast/density curve in Photoshop to restore the scene (or desired) contrast. The file is robust enough to cope with this, and should contain all the detail originally captured.