From: Gordon J. Holtslander (holtsg@duke.usask.ca)
Date: 07/21/01-10:41:51 PM Z
Hi:
Three potential solutions.
odorless fixer
There is a formula for odorless fixer. This may help if its the sulpher
odor of the fixer that bothers you. It called Kodak F-6 fixer. The
formula from
Carrol's Fact and Formulas
Water (100 d F.) 600 cc
sodium thiosulfate (hypo) 240 g
sodium sulfite (dessicated) 15 g
Acetic Acid (28%) 48 cc
Kodalk 15 g
Potassium Alum 15
Cold water to make 1.0 L
Dissolve the hypoe in the specified volume of ater at 125 degrees F. and
then add the remaining chemicals in the order given, taking care that each
chemical is dissolved before adding the next. Then dilute with water to
the required volume.
Cheap tubes
If you want to try something cheap I used home made developing tubes made
out of ordinary PVC pipes with end caps. A 3 inch diameter pipe can
process an 8 inch wide film.
For agitation I mounted 4 casters upright in a piece of plywood, two at
each end. The tube sits on the casters and is rolled by hand.
Its not light proof and getting the endcaps off can be hard - would be
easy if grips were glued to the caps.
I tried this out for some of the pinhole negatives I was processing. I am
planning on making some large panoramic cameras and wanted to see if I
could using something other than trays.
I used ortho film and processed under safelight. You would have to do
this in total darkness. Doing standard film would likely be challenging -
would have to fill and empty the tubes in the dark.
You may be able to fashion something like the BTZS tubes, see:
http://www.darkroom-innovations.com/BTZS_Film_Tubes/btzs_film_tubes.html
In the btzs documentation they say one can take the end off the tube,
under dim roomlight or safelight when development is almost complete.
They recommend stopping by placing the open tubes with film in a large
bath of stop bath.
They seem to say you can use safelight illumination with film tubes after
development.
You could make a lid/resevoir out of a short piece of tubing with a
connector fitting to attach it to the tube. Use 3 end resevoirs (for each
of developer stop and fix). Each resevoir would have to be long enough to
hold the volume of chemical needed to process the film. I needed about
150 mls to process an 8x10.
To drain and fill the tube with different chemicals you could simple
place the tube on the resevoir end, pull the tube off with the film inside
and place it on the next chemicals resevoir, tip the tube back on its side
and agitate.
You might be able to do this in the dark - or could try doing the latter
steps under safelight. It may not be practical if you are trying to do a
lot of film at once.
Post fix Tray processing in the light
I'm not sure of the next bit. Could others clarify whether this would
work?
I believe the reason film usually needs to be fixed in a tray is the the
fixer dissolves the anti-halation layer that is on the non-emulsion side
of the film. In a tube the non-emulsion side is stuck to the inner
surface of the tube, thus the fixer can't dissolve the anti-halation
layer.
It may be possible to dissolve the anti-halation layer after the film has
been fixed. You could try fixing the film in the tube. Once the film is
fixed you could fix it again in an open well ventilated area, which should
dissolve the anti-halation layer. Maybe a different chemical could be
used on the antihalation layer.
I fixed my large pinhole ortho negs in a tube an they appear to be fine.
I don't know if all the extra fixing would be a problem. A thorough wash
should deal with it though.
Hope my do-it-yourself ideas aren't too far fetched.
BTW gave my 10 year old daughter her first lesson on processing film
today. She shot and procesed an 8x10 pinhole ortho neg. Tomorrow I'll
show her how to coat and print cyanotype :)
Gord
On Fri, 20 Jul 2001, Shannon Stoney wrote:
> Now that we are on the subject of tubes and trays: the other alternative I
> have been considering for 8x10 negatives is tubes. It is true, is it not,
> that you have to remove the film from the tubes to fix the negatives in
> trays? Why can't you pour fixer in the tube and fix in the tube also?
>
> IF it is the case that you must fix the film in trays, how dark does it have
> to be? I may be able to rig up a fairly well ventilated, semi-dark room to
> do this in, but it's going to be expensive to make a corner of the garage
> totally light tight. (Also it's a rented garage and i don't want to put too
> much money into improving it.)
>
> --shannon
>
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Gordon J. Holtslander Dept. of Biology
holtsg@duke.usask.ca 112 Science Place
http://duke.usask.ca/~holtsg University of Saskatchewan
Tel (306) 966-4433 Saskatoon, Saskatchewan
Fax (306) 966-4461 Canada S7N 5E2
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