B&WPowder
Harman/Ilford Perceptol
Extra fine grain developer for when grain minimisation is critical. Expect ~1 stop speed loss. Best with Pan F Plus, FP4 Plus, Delta 100.
Temperature
20°C
18–24°C
Dilutions
3
Capacity
4
rolls per litre
Form
Powder
Characteristics
Grainvery fine
Acutancemoderate
Contrastnormal
Extremely fine grain, optimised for enlargement
Dilutions
stockReplenishable
Finest grain
1+1One-shot
Fine grain
1+3One-shot
Standard fine grain
Shelf Life
Concentrate
Unmixed powder indefinite
Working Solution
6 months in full bottles
Stock solution, reused with time increase. Lower capacity than ID-11.
Development Times
| Film | Dilution | ISO | Time | Temp |
|---|---|---|---|---|
| FP4 Plus | stock | 125 | 12m | 20°C |
| FP4 Plus | 1+1 | 125 | 15m | 20°C |
| FP4 Plus | 1+3 | 125 | 20m | 20°C |
| Ilford Delta 100 | stock | 100 | 15m | 20°C |
| Pan F Plus 50 | stock | 50 | 14m | 20°C |
| Pan F Plus 50 | 1+1 | 50 | 15m | 20°C |
| Pan F Plus 50 | 1+3 | 50 | 17m | 20°C |
| Ilford Delta 100 | 1+1 | 100 | 12m | 20°C |
| Ilford Delta 100 | 1+3 | 100 | 16m | 20°C |
Often Used For
Maximum enlargementFine grain prioritySlow/medium speed films
Limitations & Warnings
- Reduces effective film speed by ~1 stop
- Lower capacity than other developers
Descriptions combine manufacturer specifications with community experience. Subjective assessments reflect common sentiment among photographers and may not match your results.
Last verified: Jan 2026Report an error