From: Nelson Goforth (ngoforth@earthnet.net)
Date: 02/02/01-08:07:29 PM Z
>What caused the flaking of the emulsion in your use of the BTZS tubes is a
>mystery to me but but this is a very unusual problem. What film was it?
>Some films have very soft emulsions that will flake off rather easily, FP5+
>for example.
I'm using Arista 400, which is said to be the same as FP5 - so that may be
the issue. I want to develop a test set like this but stopping at various
stages (just after removing from tube, etc, etc) to see if I can find the
problem, but at this point I have to wonder if it doesn't happen as I flex
the film to remove it from the tube.
-
One teacher at my school uses something not unlike the 'brush' development
that Judy mentioned. It uses a glass or plexiglass rod to move developer
over the emulsion.
The technique:
You have a little plexiglass panel a bit larger than your negative, and
which will fit in whatever tray you choose. You also have a fat plexi rod
longer than the width of the negative. Both of these are carefully sanded
to remove any burrs. You have also a tray with each chemical. The amount
of developer should be limited, since it will be replaced for each negative
(or very large to avoid exhaustion, if you don't want to do that).
Everything is (hopefully) in a water bath to control temperature.
Very lightly wet the negative and place it on the plexi sheet, emulsion
side up. If you do this just right (the negative must be only VERY LIGHTLY
wet I found out) it will adhere and stay adhered throughout the process.
Start your timer and dip the plexi sheet into the developer. Hold the rod
in whatever way you like and gently pass it across the negative, back and
forth. The rod actually touches the neg.
At the end of the developing time lift the sheet and negative and place in
the stop bath, then the fix, following the same procedure. Once in the
fixer you can turn on the lights and peel the negative from the plexi -
dropping it into the fixer to remove any backing or whatnot.
Downsides:
Time (Each neg is done separately); Wet fingers (I suppose you could glue
on a handle, since the rod doesn't have to rotate); Darkness; Chance of
scratching (not if you carefully sand the rod - and if you keep your damned
fingernails carefully away from the neg - maybe another good reason for a
handle.
Upside:
Excellent, even results, with no streaking. This photographer shoot 11x14.
Why can you just rock the tray? I was told that the wave action at the
ends of the tray causes uneven development - and the plexi sheet slides to
each end. One possible remedy is a sheet that would not travel with the
waves.
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