Was [Leica] End of an Era - Now photographic chemicals

[s.dimitrov at charter.net (Slobodan Dimitrov)]

We're on federal property leased to the state which in turn leases it 
to the city.
It's just a case of doing whatever they say and want.
I learned long ago that trying to reason and show source material to 
functionaries is an exercise of none suchness. No need to pay high 
intensive seminar prices, one can go down to city hall  and just stand 
at the counter. It's a form of inverted bliss.
S. Dimitrov



On Apr 21, 2005, at 7:17 PM, TTAbrahams@aol.com wrote:

>  Most of the photographic chemicals in use today are rather benign. The
> developers are diluted heavily and pose no environmental threat. 
> Developers like
> Xtol and PCK are Ascorbic Acid-based and probably improve the waste! 
> D76 and the
> derivatives of that formula contain chemicals that are used in food
> processing (Sodium Carbonate) and  pool cleaning solutions (Sodium 
> Sulphite) and  are
> not dangerous for septic systems and treatment plants.
>  The biggest culprit is  the used fixer. The silver dissolved in fixer 
> can
> cause problems in septic systems and in large quantities also affect 
> treatment
> plants. Mind you, it takes 80 rolls of 35mm film to get an ounce of 
> silver in
> your fix so the volumes usually encountered in a private darkroom are 
> not
> serious. Silver recovery is possible but it is really not feasible 
> unless you are
> doing commercial volumes. I used to do it by keeping a sealed bucket
> (with a small vent pipe) with pure steel wool in it. You poured the 
> fixer in
> the bucket ensuring that the steel wool was always covered by fix. The 
> steel
> wool attracted the silver molecules and slowly "cleaned" the fix. It 
> is a
> smelly process so you have to keep the bucket outside and in the end 
> you have a
> black goo in the bottom that you could bring to a recovery plant. With 
> today's
> silver price hovering around $5-6/ounce it is not worth it unless you 
> do a
> couple of 100 rolls of film/month and lots of fiber based prints.
>  There are a couple of developers that are quite "clean". The PCK
> (unblinkingeye.com), a Patrick Gainer formulation that works very well 
> with Tri-X, Acros,
> etc.  - its main components are Vitamin C (Ascorbic Acid), Phenodine 
> (0,3
> grams for 30 rolls), Borax (a naturally occurring alkaline - 20 Mule 
> Team brand
> from Death Valley) and Sodium Hydroxide (sounds ominous but is a Kodak 
> name for
> Red Devil Lye). The PCK is diluted 8 times for use so it is virtually
> exhausted after use.
> The classic Rodinal contains some not so healthy components but with
> dilutions ranging from 1:25 to 1:125 in normal use it is again so 
> diluted that it
> poses no threat.
>  Some of the Pyro formulas are dangerous in concentrated form but once 
> they
> are in suspension with water the dilutions are so great that they are 
> rendered
> virtually harmless.
>  If you are a heavy fixer user (5-10 gallons a month) you should 
> probably do
> the right thing and take  the used fix to a collecting place rather 
> than
> jeopardising your septic tank system.
>  City systems get more "crap" into them than even the most eager 
> darkroom
> users could amass;  oil-drips, leaky radiators, detergents from 
> households,
> roadsalt after the winter, etc.
> Keep printing and processing,
> Tom A
> ---------------------
> Tom Abrahamsson
> Vancouver, BC
> Canada
> www.rapidwinder.com
>
>
>
>
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>
Slobodan Dimitrov
http://sdimitrovphoto.com