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Development time

Adox HR-50 in ADOX Atomal 49

8:30 at 20°C (68°F), stock dilution, box speed.

Start timer · 8:30
Time
8:30
Standard
Dilution
Stock
Temperature
20°C
68°F
Box speed
ISO 50
B&W

Development time

DilutionEITimeTempAgitationEvidenceTimer
Stock508:3020°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
10:389:318:307:396:486:075:32

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

Adox HR-50
Ultra-fine-grain super-panchromatic film on PET, modified by ADOX from an Agfa-Gevaert aerial emulsion; up to 280 lp/mm and usable for infrared with filtration.
Notes on this pairing
  • Datasheet names ADOX ATOMAL. Agitate for the first 30 s, then two slow tilts each minute.

HR-50 in other developers

Other films in ADOX Atomal 49