Sunday, December 11, 2011

Quick and dirty Reducer

Reducer (simple and probably not the most effective in this world...)

A simple reducer bath might come handy if one has troble with fogging, this happens sometimes with unfortunate combinations of film types and ascorbate-type developers.

The idea is to bleach away the image, and then re-develop the film in bright light, so that all of the silver is available for re-development, and in bright light, very controllable so one can stop the process after the image is back, but before the fogging is redeveloped......
The trouble with traditional recipes always was toxicity, chemicals was used that posed a definite threat if misused, and in ou4r search for a simple alternative, these two recipes cropped up.

I haven't tessted and compared these with the old industry standard, Farmer's reducer, so these simple recipes most likely ain't too effective, but, they should work and make do if needed.

I have no idea of how these will keep in solution, but they are both cheap and simple, and can be discarded after use, and one should also be able to just dump this in the drain since no deadly poisons are used.

Eder suggest :

Water 750 ml
Copper sulphate 50 g
Sodium chloride 50 g
Water to 1000 ml

Agfa suggest :

Water 750 ml
Copper sulphate 100 g
Sodium chloride 100 g
Sulpuric acid conc. 25ml
Water to 1000 ml

Negatives to be treated in subdued light, preferably a darkroom with darkroom lightning, until one has a white-color "image", then be watered for 2 .. 3 min (3 changes of water, agitated like the Ilford method).

Then the image must be RE-development in daylight, in a normal or a finegrain developer, until satisfaction, but before one get fog, and then a normal acid stop, fixation and a thorough washing, like normal development.

Make a careful note bleaching and reduction will save some of the picture qualities only, one will ALWAYS loose picture quaklity with this procedure!  Loss of detail sharpness and large grain are traditionally connected with this, but the use of a fine gran RE-developer sometimes negates the large grain, this usually comes with a cost of low contrast.

All taken together this technique should be carefully considered before one risks destroying valuable negatives!

The ingredients :

Concentrated sulphuric acid is impossible to get over here, after 09.11.01 and 22.07.11, since it is a effectice raw material for explosives production.

Instead we use battery acid (33%) multiply with 3 and simply fill with water to 1000ml ,
Copper sulphate should be available at Radio Shack, it was used in making amatuer printed circuits back in the 1970's AFAIR.
Sodium chloride is ordinary table salt! Can't be simpler than that!
And  finally a viable USE for table salt in photography!


  1. Aside from the sodium cloride, this is strikingly similar to the bleach in reversal processing.

    What does the salt do to the chemistry?

  2. I imagine it is there to supply chloride for rehalogenating the silver, in order to have it available for redevelopment.

    In reversal processing the idea is to get rid of silver, expose untouched silver halide and develop that in living color, isn't it?

    AFAIK, the bleach is not similar at all, that was the rationale behind this post.