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Development time

Foma Bohemia Fomapan 100 Classic in Microphen

5:00 at 20°C (68°F), stock dilution, box speed.

Start timer · 5:00
Time
5:00
Standard
Dilution
Stock
Temperature
20°C
68°F
Box speed
ISO 100
B&W

All 4 times

DilutionEITimeTempAgitationEvidenceTimer
Stock1005:0020°C / 68°FStandardManufacturerChecked Oct 2026Start timer
Stock1002:0030°C / 86°FStandardManufacturerChecked Oct 2026Start timer
1+11008:0020°C / 68°FStandardManufacturerChecked Oct 2026Start timer
1+310013:0020°C / 68°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
6:155:365:004:304:003:363:15

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
1+1150 ml developer + 150 ml water250 ml developer + 250 ml water
1+375 ml developer + 225 ml water125 ml developer + 375 ml water

How they work together

Microphen
Fine grain, moderate acutance, normal contrast. Fine grain with an effective speed increase.
Foma Bohemia Fomapan 100 Classic
Traditional cubic-grain emulsion with high resolving power and a wide range of halftones (Foma datasheet: RMS 13.5, 110 lines/mm). Rated ISO 100/21 but the maker says it gives good results one stop over (EI 50) or two stops under (EI 400) with no change in development.
Notes on this pairing
  • Microphen stock. Datasheet gives 5 to 7 min; lower figure used.
  • Microphen stock. Datasheet alternative at 30 °C.
  • Microphen 1+1. Guide gives 8 to 9 min; lower figure used (lower value gives lower contrast). Spiral tank: continuous for the first 30 s, then 10 s each minute.
  • Microphen 1+3. Guide gives 13 to 14 min; lower figure used (lower value gives lower contrast). Spiral tank: continuous for the first 30 s, then 10 s each minute.

Fomapan 100 Classic in other developers

Other films in Microphen