Notes on Film Development

Marko van Treeck

2026-06-16

Notes on Film Development

Times

Film	EI	Developer	Dev’ Time @ 20°C	Comment
Fomapan 100	100	Excel	3:15
Fomapan 100	100	Rodinal 1+50	8:30
Fomapan 400	400	Excel	7:00	May look thin, but Foma’ 400’s max. density is just not very high.
Rollei Infrared	100	Rodinal	7:00

Non-Recommended Times

Film	EI	Developer	Dev’ Time @ 20°C	Comment
Fomapan 100	100	Excel	6:00	I don’t know how this made it into the datasheet, it’s super dense!
Fomapan 400	400	Excel	8:15	Muddy highlights in high-contrast scenes.

Formulas

Temperature Compensation

The time to develop a film at temperature $T$ in degrees, if $t_{20°}$ is the development time at 20°, is

$t_T = t_{20°} \cdot 1.1^{T/°-20}$

Pushing and Pulling

The development time when pushing a film $Δs$ stops is

$t = t \cdot 2^{Δs / 2}$ ,

so pushing a film two stops roughly doubles the development time.

Specific Films

Fomapan 100

Film	Developer	Dev’ Time	Dev’ Temp	$D_\textrm{min}$	$D_\textrm{max}$
Fomapan 100	Rodinal 1+50	5:45	24°	-1.1EV	-6.7EV

Here is the same scene, three times, shot on a Canon EOS 300 using evaluative metering. The scene was taken in harsh sunlight, on a June day at around 15:00. The black point was set to match $D_\textrm{min}$ of the negative, the white point was set to $D_\textrm{max}$ of each specific frame.