[LargeFormat] A better way

[Wilkes, Don MSER:EX]

>   The anti-halation backing on most B&W film is a dye in the anti-curl
> gelatin coated on the back of the support. It is not removed but
> decolorized by the developer. The fixer usually will 
> decolorize it too, but
> more slowly. 

AH!  This might explain something I found curious this year.  A friend had
shot some Fuji Neopan 1600 (35mm), had a lab process the negs, and brought
it over to my darkroom to make some prints.  I was somewhat surprised to see
that the base of this film was very clear, not the usual grey.

Six months later, I had a reason to shoot some of this film for the first
time, and was startled to find that when I processed it (in ID-11), it had
the usual grey colour in the unexposed areas.  Could it be that the lab had
chosen a developer/fixer combination that produces that clear-base look?

This could be a potentially useful bit of knowledge. There are some projects
in the back of my mind for making b&w slides from negs, using a slide
copier.  Knowing how to pick a developer to remove that colour cast would be
great!

So, if you have more details on this, Richard, I'd be delighted to hear
about it.

Cheers,
\donw in Victoria