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Ian Marsh
29th January 2012, 11:19 AM
can somebody please tell me the quantity to water used to use this as a bleach ,(localised) including water temp when mixing

thanks

Tony Marlow
29th January 2012, 12:53 PM
I mix up Potassium Ferricyanide as a 10% solution and sodium thiosulphate as a 10% solution. To make a Farmers Reducer I mix the 10% solutions as follows, 1 part ferri, 5 parts Sodium thiosulphate (hypo), and 6 parts water. In Tim Rudman's book he says 10ml ferri with 100ml hypo. I think both methods give similar answers 1 part ferri to 10 parts liquid. If you you don't want the bleaching to be irreversable I guess use the same ratios of liquid but omit the sodium thiosulphate crystals. I don't think these ratios are cast in stone, stronger solutions act quicker and weaker dilutions slower. I use the water at room temperature.

Tony

Adrian Twiss
29th January 2012, 04:35 PM
For localised bleaching I, like Tony, mix a 10% solution. When I want fine control I further dilute it 1:4. I mix at 20 deg C. After bleaching if I am satisfied with the results I re-fix the print, then hypo clear and wash.

Stoo Batchelor
29th January 2012, 09:40 PM
Just to add to what has already been said. As I tone many of my photographs, I will already have the stock that Tony and Adrian have already mentioned, only with bromide added. (10g ferri, 5g Potassium bromide mixed in water, and topped up to 100ml)

To bleach locally I just put 5ml of fixer at 1:9 in to a small container, usually a lid of some sort, and then drop 1,2 or 3 drops of the bleach from a pippette in to it. The golden rule is that if it bleaches to your requirement on the first application, then the bleach is too strong. Two or three applications are better, slowly building up to what you want.

Stoo

Dave miller
30th January 2012, 08:08 AM
Just to add to what has already been said. As I tone many of my photographs, I will already have the stock that Tony and Adrian have already mentioned, only with bromide added. (10g ferri, 5g Potassium bromide mixed in water, and topped up to 100ml)

To bleach locally I just put 5ml of fixer at 1:9 in to a small container, usually a lid of some sort, and then drop 1,2 or 3 drops of the bleach from a pippette in to it. The golden rule is that if it bleaches to your requirement on the first application, then the bleach is too strong. Two or three applications are better, slowly building up to what you want.

Stoo

Well put. The other golden rule is "when it's gone, it's gone!":)