The DARKROOM COOKBOOK, Third Edition

STOCK SOLUTION #4
Metol, 6.5 g
Sodium sulfi te, 3.8 g
Water to make 750.0 ml
Formulas 307
To use, prepare the intensifi er solution as follows:
Add 1 part of Solution #2 to 1 part of Solution #1, stir well. A white precipitate will form but
will dissolve with the addition of 1 part of Solution #3. Allow the mixture to stand for a few
minutes until clear.
Add, while stirring, 3 parts of Solution #4. The intensifi er is ready for use, and the fi lm
should be treated immediately. The mixed solution is stable for approximately 30 minutes at
68F/20C.
After intensifi cation, immerse the fi lm for 2 minutes in a 30% plain hypo bath (30.0 grams
of sodium thiosulfate to 100.0 ml of water).
I recommend not intensifying with silver beyond 10 minutes, even though Kodak claims
it can be used up to 25 minutes. If you do over intensify use two-solution Farmer’s Reducer
R-4b to reduce or eliminate the silver.
NOTE: When mixing Stock Solution #4, add a pinch of the sodium sulfi te fi rst, stir in the
metol until well dissolved, and then add the balance of the sulfi te.
FORMULA #180
Kodak In-6
Intensifi er for coarse-grain fi lm.
This intensifi er produces the greatest degree of intensifi cation of any known single-solution
formula when used with high-speed negative materials. The intensifi ed image is a brownish
hue and is not completely permanent. However, it will remain in satisfactory condition for
several years if stored properly. The intensifi ed image is destroyed by acid hypo; under no circumstances
should the intensifi ed negatives be placed either in fi xing baths or in wash water
contaminated with fi xing bath. Kodak In-6 Intensifi er is not suitable for fi ne-grain materials or
for use when only moderate intensifi cation is desired.
SOLUTION A
Distilled water at 68F/20C, 750.0 ml
Sulfuric acid, concentrate, 30.0 ml
Potassium bichromate, anhydrous, 22.5 g
Water to make 1.0 liter
* Potassium bichromate is an allergen to some people and a suspected carcinogen. See precautions
under potassium bichromate in Pharmacopoeia.