Moersch Bleach or Farmer's Reducer?

[logan2z]

I want to experiment a bit with bleach in order to reduce density in areas of my prints, and there appears to be two primary choices:

1) A bleach like the one from Moersch which is a combination of Potassium Ferricyanide/Potassium Bromide

Moersch Bleach Concentrate - 100 ml

Moersch Bleach Concentrate - 100 ml - Bleach concentrate: ferricyanide/potassium bromideDilution: between 1+10 and 1+100

www.freestylephoto.com

2) Farmer's Reducer.

Formulary Spot Reducer II - 375 ml

Formulary Spot Reducer II - 375 ml - Formulary's Spotting Reducer II For Paper is the classic Farmer's Reducer. The solution acts by conversion of the silver metal in the print to silver bromide. The reducer can be used to…

www.freestylephoto.com

My understanding is that the Potassium Bromide in a bleach like the one from Moersch allows the print to be redeveloped, while the hypo in Farmer's reducer would obviously prohibit re-development. Having the option to re-develop sounds appealing. The Moesrch bleach also comes as a liquid concentrate which I prefer to mixing powdered chemicals, which is necessary with Farmer's Reducer. I do understand that I will need to re-fix a print if bleached using the Moersch product.

Are there any downsides to the Moersch Bleach? I don't hear much about it. Does it possibly have a shortened shelf life due to it being in liquid form? Any health/safety concerns with using a product containing ferricyanide? I understand that it needs to be kept away from strong acids and heat, but are there any other precautions required when using it (other than not eating it )?

 

[Alex Benjamin]

Does it possibly have a shortened shelf life due to it being in liquid form?

I'm pretty sure the shelf life of the potassium ferricyanide/potassium bromide mix is longer than my own shelf life .

My understanding is that the Potassium Bromide in a bleach like the one from Moersch allows the print to be redeveloped, while the hypo in Farmer's reducer would obviously prohibit re-development.

Absolutely right. Adding the sodium thiosulfate prohibits redevelopment. Mixing the sodium thiosulfate with the potassium ferricyanide/potassium bromide mix is also what shortens the longevity of the bleach.

That said, I've never tried the Moersch, so I have nothing to say about that specific product.

 

[DREW WILEY]

The PF "Farmer's Reducer" is way stronger than the former Kodak version if you follow their own tip sheet. I dilute considerably more for use than PF recommends. Mixing the powders into separate A&B concentrates is easy enough; and these last a long time in separate glass bottles. The working solution should be mixed in only enough quantity you actually need right before use.

 

[Guillaume Zuili]

I use the bleach from Moersch. Works perfectly well and keeps acting for a long time when diluted.
So no need to worry about the concentrate. Yes if you don't redevelop you need to fix the print.