Divided D-76 Style Film Developer - rec.photo.darkroom

Message from discussion Divided D-76 Style Film Developer

Peter

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More options May 5, 4:21 pm

Newsgroups: rec.photo.darkroom

From: Peter <w2...@hotmail.com>

Date: Sun, 4 May 2008 23:21:06 -0700 (PDT)

Local: Mon, May 5 2008 4:21 pm

Subject: Re: Divided D-76 Style Film Developer

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On May 5, 7:56 am, jch <j...@nowhere.net> wrote:

> _____
> Hello All,

> I have been reading about divided developers for film. Never tried it;
> looks promising though! Do any of you in this group have any experience
> with this approach? The reason for my interest is the fact that i live
> in the country and that my house disposes of waste water via a septic
> tank system. Hence, i want to minimise the amounts of photographic
> chemicals entering the tank in case they kill the microbes.

> Below is a divided developer formula; a variant on D-76 where BATH A and
> B can be kept for a long time:
> A BATH
> Water at 125F 3 cups
> Metol 1/2 tsp
> Sodium sulfite 2 TBL
> Hydroquinone 2 tsp
> Potassium bromide 1/8 tsp
> Cold water to make 1 quart

> B BATH
> Water at 80-100F 3 cups
> Sodium sulfite 2 TBL
> Borax 2 TBL
> Cold water to make 1 quart

> Process 2-4 minutes in A BATH, and the same time in B BATH, both at 68F.
> Agitate for 15 sec initially, and for about 5 seconds every half
> minute. Stop bath is not recommended after B BATH, a quick 1 min rinse
> in water is enough. Fix the film in the usual manner.

> A BATH will last indefinitely, and B BATH can be used for 20-30 rolls of
> film before any change in contrast or density should be noticed.

> There is also a phenidone version of this formula to obtain increased
> film speed.

> --
> Regards / JCH

Not sure what to make of this, but at least A BATH will deteriorate
with use and with time. The usual interpretation of "indefinitely" in
"A BATH will last indefinitely" is misleading. The lifetime may be a
little uncertain, but it will steadily deteriorate.

As B BATH becomes contaminated with A BATH it will at least look
ugly.

Metol and Hydroquinone decompose in air. They are the more
troublesome parts of your mix (although I don't necessarily recommend
drinking a lot of borax). Unless you process a whole lot of film, you
may be just as well served by letting the used developer sit in a tray
for a few days before pouring it down the sink.

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