Re: Lith film and base density

Tom,

I make continuous tone prints on Freestyle's APSH film for display in
lightboxes and ran into the same problem you seem to be experiencing. You
can test for fog by processing an unexposed sheet as normal and comparing it
(via densitometer) with one cleared in fixer. I found, in my case, that the
problem was three fold: the safelight, general room light, and the
developer. I use a Thomas safelight (b&w filters) with the vanes closed in a
10x10 darkroom - even with it as far from the film as possible it was
fogging the film; blocking 1/2 the output helps quite a bit. For general
room lighting, I was using a surface mounted fluorescent fixture and found
that even after being off for 30 minutes it was still giving off light - I
switched to halogen track lights to solve that part of the problem. I
started using Dektol diluted 1+15 @ 70F for 2-1/2 minutes and when I
switched to Ansco 130 diluted 1+1 @ 70F for 5 minutes fb+f went from about
.07 to about .03 density.

Hope this helps,

Scott Wainer
smwbmp@starpower.net

>
> Somewhere "back in time" I started doing enlarged negs with this
> material and developing it for a few minutes in diluted HC-110 film
> developer followed by a variable time in diluted zone VI paper
> developer. So, I will try each developer alone and see if one of them
> is my "fog" creator. If I were still using APSH for enlarged negs, the
> fog would be perfectly acceptable. As I'm now using it for a final
> display/print I would like it be be more transparent in the clear areas.
>
> --------------
> Tom Ferguson
> http://www.ferguson-photo-design.com
>
>
Received on Sat Dec 6 04:56:50 2003