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wiki:darkroom:chemistry:formulas:farmers_print

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Farmer's Reducer (full print bleaching)

For bleaching och full prints.

Increases contrast and clears highlights

Preparations

Prepare stock solutions as described below:

Part A

x1 x2 x4
Potassium Ferricyanide 1.2 gr 2.5 gr 5 gr
Potassium Bromide 0.6 gr 1.25 gr 2.5 gr
Water, to make 5 ml 10 ml 20 ml

Part B

x1 x2 x4
Sodium Thiosulphate (Hypo) 30 gr 60 gr 120 gr
Water, to make 120 ml 240 ml 480 ml

Finally, prepare working solution as specified below:

Working solution

Part A, 5 ml
Part B, 120 ml
Water, to make 1000 ml

To get a weaker and more slowly acting solution, reduce the amount of Part A. The solution is active for approx 10 min.

Instructions for use

Immerse the wet print in a tray of working solution. Don't agitate, agitation tend to cause an uneven result with more bleach on print edges. Treat for approx 5-10 sec. Thereafter, rinse the print in running water and evaluate. Repeat if necessary. When satisfactory, fix and wash the print as normally.

A strong and rapid bleach is better for increasing (local) contrast. A weaker and more slowly working bleach is better for overall print reduction.

Notes

This recipe is from Darkroom Cookbook[1], Formula #173.


1 ^ a Steve Anchell, 2008. The Darkroom Cookbook. 3. Focal Press, pp.359, ISBN 978-0-240-81055-3.
wiki/darkroom/chemistry/formulas/farmers_print.1651398238.txt.gz · Last modified: 2022/05/01 11:43 by henpe

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