Bill Williams CD4 Color Film Developer

Published in May 21, 2008 by Bill Williams at APUG, here is his recipe:

«Water 500ml @ approx 112 degrees
Sodium Sulfite (A) .5 grams (approx 1/8 tsp)
CD4 .35 grams (approx 1/8 tsp)
Potassium Iodide 1.8 milligrams
Potassium Bromide .25 grams
Potassium Carbonate (A) 4 grams (approx 2/3 tsp)»

The recipe is very minimal and precise about the amounts in grams and apparently  not accurate with fractions of tsp. But reading above the recipe, one can understand what he means. He used graduated inox recipients to measure exact solutions of Potassium Carbonate, Sodium Sulfite and Potassium Bromide. I only don't understand how he measured Potassium Iodide from a 1% solution.

I prepared following separate 500 ml each solutions:

• 50 grams CD4 and 1,5 grams Sulfite as preservative only
• 50 grams Sodium Sulfite
• 50 grams Potassium Bromide
• 50 grams Potassium Carbonate

I already had a 2% solution of Potassium Iodide. So I took 5 ml (that contains 100 mg) and add water to make 100 ml, so I ended with a 0,1% solution. To use 1.8 mg, I need 1,8 ml of this solution.

With a 5 ml syringe, I measure following amounts to prepare 500 ml of this developer:

• 5 ml Sulfite 10% solution
• 3.5 ml CD4 10% solution
• 1.8 ml of Iodide 0,1% solution
• 2,5 ml Bromide 10% solution
• 40 ml Carbonate 10% solution

One of the last results