[LargeFormat] Making Water in the Dark

[Les Newcomer]

Shamelessly copied from "The (B&W)Film Developing cookbook"

"...film processing should ideally take place in high salt solutions at or
near the ph of the developer.

there are several advantages to using an alkaline fixer:
1. Alkaline fixers do not dissolve image-bearing silver

2.alkaline fixers allow shorter washing times. Removal of hypo is faster
than when an ordinary fixer plus a hypo clearing agent is used. Hypo is down
to archival levels after a minute of washing. but film should be wahid a
total of three minutes to ensure all developer reside is removed.

3. Keeping the entire system either neutral or alkaline, from alkaline
develeoper, neutral water stop, alkaline fixer and neutral final washt
without HCA) will improve the permanence of all films and papers because the
thiosulfate does not mordant to the silver image or base.

4. Alkaline fixers have greater capacity than acid fixers.

5. alkaline fixers are easier to formulate and more stable as thiosulfates
are more stable in analkaline solutions.

6. Alkaline fixers can be formulated to have a very low ordor"


The only commercially available fixer is Photographer's Formulary's TF--4

But here is TF-3.  It's more alkaline than TF-4 and has a faint ammonia
odor.
Ammonium Thiosulfate 800ml
Sodium Sulfaite anhydrous 60g
Sodium metaborate 5g
water to make 1 liter

working solutins  Dilute 1:4 with water.



""...Immediatley after development wash in running water for 60 seconds. Fix
film for three times the clearing time usually 3-5 minutes. Wash for 3
minutes. A hypo Clearing agent is not required"


I've got a friend that eliminates the water stop, goes directly into the
fix.  After 6 months even though the fix was still working well, he finally
replaced it so he could sleep nights.

he keeps telling me the whole world is wrong.  "Hey the best way to get the
acid out of the paper is not to put it in!!!!!!"



Les


> From: "Frank Filippone" <red735i@earthlink.net>
> Reply-To: largeformat@f32.net
> Date: Wed, 3 Apr 2002 08:29:23 -0800
> To: <largeformat@f32.net>
> Subject: RE: [LargeFormat] Making Water in the Dark
> 
> I think for B+W you need to read the latest in Ilford's literature on
> archival printing.   They propose that we fix too long, getting the fixer
> deep into the paper, causing long wash times to remove that fixer.  Their
> proposal is to.use a strong quick ix, folloed by a 2 stage quick wash....
> and they claim this is archival in process.....
> 
> For film, JOBO has published that it is the NUMBER of changes of wash that
> get rid of the fixer.... they state 20 changes of water is sufficient to
> archivally process B+W films.....  At 170mL per wash, that is still about a
> gallon......
> 
> I think some reading in this area will prove to somewhat alleviate the
> problem, but whatever you do, don;t recycle the water into yor examining
> room... the patients would prefer not to have this kind of "fixed" teeth.
> 
> Frank Filippone
> red735i@earthlink.net
> 
> 
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