The DARKROOM COOKBOOK, Third Edition

FORMULA #194
Kodak SH-5
Formulas 315
Prehardener
For high-temperature processing
Water, 900.0 ml
*Kodak Anti-Fog No. 2, 0.5% solution 40.0 ml
Sodium sulfate, 50.0 g
Sodium carbonate, monohydrate, 12.0 g
Water to make 1.0 liter
Formaldehyde, 37% (formalin), 5.0 ml
* Kodak Anti-Fog #2 is 6-nitrobenzimidazole nitrate. To make a 0.5% solution, dissolve 1 gram in
200.0 ml of distilled water.
To use, soak the exposed fi lm in the prehardener for 10 minutes with moderate agitation.
Then drain the fi lm for a few seconds, immerse in water for 30 seconds, drain thoroughly,
and immerse in the developer. In general, developers such as Kodak D-76 may be used up to
95F/35C. Above 95F/35C it may be better to use developers specifi cally formulated for tropical
developing (Tropical Developers High-Temperature Processing up to 105F/40C, above).
The following are developing time adjustments for use with a prehardener at temperatures
between 75F/24C and 95F/35C:
75F/24 Use normal developing time recommended for processing without prehardener
at 68F/20C
80F/27 Develop for 85% of time at 68F/20C
85F/29 Develop for 70% of time at 68F/20C
90F/32 Develop for 60% of time at 68F/20C
95F/35 Develop for 50% of time at 68F/20C
After development is complete rinse and fi x in an acid-hardening fi xing bath such as Kodak
F-5. Wash and dry as usual.
At temperatures above 95F/35C, increase the 6-nitrobenzimidazole content of the prehardener
up to double the normal formula concentration to control fog. Process as just
described, using a low-activity developer to avoid short processing times. The average development
time at 110F/43C, after prehardening, is 25% of the normal time at 68F/20C.
NOTE: The entire bath, with the exception of the formalin, may be kept as a stock solution.
Just before use, add 5.0 ml of the formalin to each liter and mix thoroughly.
FORMULA #195
Kodak ST-1
Residual Silver Test Solution
An overworked fi xing bath contains complex silver thiosulfate compounds that can be
retained by negatives or prints and cannot be removed completely by washing. This formula