First published on 16.09.2012
Review on 27th Feb. 2013

Recipe:

Use allways cold preboiled water.

CS (stock solution):

5 g Sodium Sulfite
200 g cheap soluble coffee
200 g Vit. C
Water to make 1 Liter
Preparation: Put water on fire and let it boil for 10 minutes. Then wait until the water is cold and mix by order, having sodium sulfite in water will prevent oxidation of coffee and vit. C. Coffee is no problem to dissolve but with vit.C you must count on production of many foam, so use a large container for the mix. Of course you may divide the recipe by 2 or by 4. 250 ml will last for months.
This mix will survive for months, but more if kept in the refrigerator. This is not a developer alone, it needs a basic solution to work. But you only use a small portion of it, each time. The work solution may not develop many films it is tought as one shot.

Example of a tested working solution for film with CS:
5% solution of Sodium Carbonate, aka Soda
1g/L of Potassium Bromide
10 ml/L of the concentrate solution CS
Reference time (depending on film): 30 minutes at 20ºC.

Example of preparation of a 500ml of this working solution:

In about 300 ml water disssolve 25g Sodium Carbonate and add 0,5 g of Potassium Bromide. Yes 0,5 g is difficult to measure but you may have a stock solution of just Potassium Bromide at 10% and then use 5ml of this, measured with a siringe as a suggestion. Then add 5 ml of CS, the concentrate solution. Yes, only 5 ml, that is to say, you are using only 1 g coffee and 1 g vit C pro film!

In fact, I call CS only the first part of the developer. For the second part you may change according to film or whatsoever. For instance, I am convinced that a 1% solution of sodium hydroxide would work too. Or you may put a mix of sodium sulfite and sodium carbonate and borax and so on. For film it is allways good to use Potassium Bromide as anti-fogant.