Development time

CatLABS CatLABS X Film 320 (120/Sheet) in Rodinal

19:00 at 20°C, 1+50 dilution, box speed.

Start timer · 19:00

Time

19:00

Standard

Dilution

1+50

Temperature

20°C

Box speed

ISO 320

B&W

All 3 times

Dilution	EI	Time	Temp	Agitation	Timer
1+50	320	19:00	20°C / 68°F	Standard	Start timer
1+25	320	9:00	20°C / 68°F	Standard	Start timer
1+25	1600+2⅓ stops	17:00	20°C / 68°F	Standard	Start timer

EI is the speed the film was rated at when shooting. Times marked “not yet verified” come from secondary sources and haven’t been checked against a manufacturer datasheet.

Other temperatures

18°C	19°C	20°C	21°C	22°C	23°C	24°C
23:45	21:17	19:00	17:06	15:12	13:41	12:21

Calculated from the 20°C time using Ilford’s temperature compensation factors, not taken from a datasheet. Most B&W developers behave well between 18°C and 24°C.

Mixing

Dilution	300 ml (one 35mm roll)	500 ml (one 120 roll)
1+50	5.9 ml developer + 294 ml water	9.8 ml developer + 490 ml water
1+25	12 ml developer + 288 ml water	19 ml developer + 481 ml water

How they work together

Rodinal: Prominent grain, high acutance, full film speed, variable contrast. Sharp, dramatic, distinct edge effects.
CatLABS CatLABS X Film 320 (120/Sheet): Different emulsion from the 35mm version (which is Kodak Double-X). Origin unclear - likely aerographic stock with finer grain.
Notes on this pairing: Maximum speed; maker says results unpredictable.

CatLABS X Film 320 (120/Sheet) in other developers

510-Pyro