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Development time

Foma Bohemia Fomapan 400 Action in Perceptol

9:00 at 20°C (68°F), stock dilution, box speed.

Start timer · 9:00
Time
9:00
Standard
Dilution
Stock
Temperature
20°C
68°F
Box speed
ISO 400
B&W

All 2 times

DilutionEITimeTempAgitationEvidenceTimer
Stock4009:0020°C / 68°FStandardManufacturerChecked Oct 2026Start timer
Stock4004:0030°C / 86°FStandardManufacturerChecked Oct 2026Start timer

EI is the speed the film was rated at when shooting. Evidence says where each time comes from: the manufacturer’s own data, a named test, a compilation or several agreeing reports (community consensus), or one person’s report. Times marked “not yet verified” come from secondary sources and haven’t been checked against a manufacturer datasheet. Where sources give different times, every one is listed and marked “sources differ”.

Other temperatures

18°C64°F19°C66°F20°C68°F21°C70°F22°C72°F23°C73°F24°C75°F
11:1510:059:008:067:126:295:51

Calculated from the 20°C (68°F) time using Ilford’s temperature compensation factors, not taken from a datasheet. Most B&W developers behave well between 18–24°C (64–75°F).

Mixing

Dilution300 ml (10.1 fl oz) (one 35mm roll)500 ml (16.9 fl oz) (one 120 roll)
StockUse as mixed, undilutedUse as mixed, undiluted

How they work together

Perceptol
Moderate acutance, normal contrast. Extremely fine grain, for when a loss of film speed is acceptable.
Foma Bohemia Fomapan 400 Action
Traditional cubic-grain 400 film (Foma datasheet: RMS 17.5, 90 lines/mm). Rated ISO 400/27; the maker says it gives good results from EI 200 to EI 1600 without changing development.
Notes on this pairing
  • Perceptol stock. Datasheet gives 9 to 10 min; lower figure used.
  • Perceptol stock. Datasheet alternative at 30 °C.

Fomapan 400 Action in other developers

Other films in Perceptol