B&WPowder
Harman/Ilford Microphen
Speed-enhancing developer with fine grain retention. Effective half to full stop speed increase depending on film.
Temperature
20°C
18–24°C
Dilutions
3
Capacity
10
rolls per litre
Form
Powder
Characteristics
Grainfine
Acutancemoderate
Contrastnormal
Good with effective speed increase
Dilutions
stockReplenishable
Maximum speed increase
1+1One-shot
Slight speed increase
1+3One-shot
Standard results
Shelf Life
Concentrate
Unmixed powder indefinite
Working Solution
6 months in full bottles
Stock solution, reused with time increase
Development Times
| Film | Dilution | ISO | Time | Temp |
|---|---|---|---|---|
| Delta 3200 | stock | 3200 | 9m | 20°C |
| Delta 3200 | 1+1 | 3200 | 12m 30s | 20°C |
Often Used For
Speed increase (up to 1 stop)Push processingFast films
Limitations & Warnings
- Powder requires mixing
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