Farmer's reducer instead of classic bleach

norm123 · Feb 21, 2015

Hi

I never try the farmer's reducer but I know that is a bleach. Can I use it instead a classic bleach, i.e. potassium bromide and potassium ferricyanide. There is potassium ferricyanide and
sodium thiosulphate anhydrous in this product. What can I expect if I use it for a selenium/bleach. I used this process (selenium/bleach) and I was happy with the result (see picture).

https://www.flickr.com/photos/norm1thestorm/16210385250/

Regards

Normand

Rudeofus · Feb 22, 2015

Farmer's reducer is a BLIX, i.e. not only does it convert the metallic Silver into Silver ions, it also removes the Silver ions from the print by binding them in a water soluble Thiosulfate complex. Contrary to that, the bleach you suggested converts metallic Silver into Silver Bromide, which is insoluble but not stable in room light. If you want to get the silver out of your print, you can use bleach, then wash, then rapid fixer to dissolve the Silver Bromide. If you want to use the silver for toning purposes (e.g. sulfur toner), you can't use Farmer's reducer but have to use a rehalogenating bleach.

To make things even more confusing, there are rehalogenating bleaches used in color processing (C-41, E-6), which also contain silver solvents, and which therefore can't be used as rehalogenating bleaches for B&W toning except for very special effects.

My recommendation would be: until you somewhat understand the chemistry behind these bathes, either stick to established recipes, or prepare yourself for surprising results.

norm123 · Feb 22, 2015

Rudeofus said:
Farmer's reducer is a BLIX, i.e. not only does it convert the metallic Silver into Silver ions, it also removes the Silver ions from the print by binding them in a water soluble Thiosulfate complex. Contrary to that, the bleach you suggested converts metallic Silver into Silver Bromide, which is insoluble but not stable in room light. If you want to get the silver out of your print, you can use bleach, then wash, then rapid fixer to dissolve the Silver Bromide. If you want to use the silver for toning purposes (e.g. sulfur toner), you can't use Farmer's reducer but have to use a rehalogenating bleach.

To make things even more confusing, there are rehalogenating bleaches used in color processing (C-41, E-6), which also contain silver solvents, and which therefore can't be used as rehalogenating bleaches for B&W toning except for very special effects.

My recommendation would be: until you somewhat understand the chemistry behind these bathes, either stick to established recipes, or prepare yourself for surprising results.

Thank you
Sure, I need to get more readings about chemistry. I know that I don't understand fully all of bathes in the darkroom process. Any way I'll stick on established recipes and read more about BLIX.

Regards

Farmer's reducer instead of classic bleach

norm123

Rudeofus

norm123

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