Chlorhydroquinone alone is not often used as a negative developer, but the following formula gives good results.
| Ingredient | Quantity | |
|---|---|---|
| Sodium sulphite anhydrous | 100 | grams |
| Potassium carbonate | 150 | grams |
| Chlorhydroquinone | 50 | grams |
| Water to make | 1 | liter |
| Mix chemicals in order. | ||
For strong contrast, dilute with 3 parts of water. For softer negatives dilute 1:5. Add 5 mililiters of 10% potassium bromide solution to 0.5 liters of working solution.
The image appears in 20 seconds and development is complete in 4–5 minutes at 18.5°C.