This positive developer is suitable (or all papers, which are intended to give warm-black tones, e.g., chamois contact paper (gas-light), portrait contact and enlarging papers (chloro-bromide).

Focal paper developer for warm-black tones, working solution
Mix chemicals in order.
Sodium sulphite anhydrous37.5grams
Sodium carbonate anhydrous37.5grams
Potassium bromide2grams
Sodium chloride5grams
Water to make1liter

Use: In general, the desired warm tones are produced by the undiluted solution, but with some papers, dilution with an equal quantity of water is recommended, otherwise the tones may be too cold.

Times of development:

  • For contact papers : 1.5 minutes.
  • For enlarging papers : 2.5–3 minutes.

Note: The qualities of the developer may be enhanced by the addition of a developer improver.