Development time

Ilford Delta 400 in Rodinal

9:00 at 20°C, 1+25 dilution, box speed.

Start timer · 9:00

Time

9:00

Standard

Dilution

1+25

Temperature

20°C

Box speed

ISO 400

B&W

All 2 times

Dilution	EI	Time	Temp	Agitation	Timer
1+25	400	9:00	20°C / 68°F	Standard	Start timer
1+50	400	20:00	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
11:15	10:05	9:00	8:06	7:12	6:29	5:51

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+25	12 ml developer + 288 ml water	19 ml developer + 481 ml water
1+50	5.9 ml developer + 294 ml water	9.8 ml developer + 490 ml water

How they work together

Rodinal: Prominent grain, high acutance, full film speed, variable contrast. Sharp, dramatic, distinct edge effects.
Ilford Delta 400: Modern T-grain film with fine grain and high sharpness. Core-shell crystal technology provides excellent detail. More contrast than HP5 with less pushability.
Notes on this pairing: Non-Ilford developer. Times are a general guide per Ilford.

Delta 400 in other developers

D-76