Tools
Development calculator
Choose a film and a developer, then the dilution, speed and temperature the time was published for. You get the maker’s time with the datasheet it came from — and, if you need them, corrections for a warmer bath (NegaKit’s rule) or a reused developer (the maker’s own rule, where it publishes one).
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Film
ADOX CHS 100 II · ISO 100 · B&W
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Developer
Only developers with published times for this film.
ADOX Atomal 49 4 times ADOX FX-39 Type II 3 times ADOX Rodinal 7 times ADOX Silvermax Developer 4 times Fomadon Excel W27 1 time Fomadon LQN 1 time Fomadon P 1 time Fomadon R09 1 time Ilford ID-11 3 times Ilford Ilfotec DD-X 2 times Kodak D-76 6 times Kodak HC-110 6 times Kodak XTOL 2 times SPUR HRX 1 time -
Dilution
The only one published for this choice.
1+17 -
Speed
The only one published for this choice.
EI 100 box speed -
Temperature
The only one published for this choice.
20 °C
How the numbers are worked out
Only what is published
Every time is a maker’s or a source’s own, read off the datasheet linked beside it. Speeds, dilutions and temperatures are the ones published: nothing is extrapolated, so a push nobody published is simply not on the list.
A warmer or cooler bath
For black-and-white film only, and only between 18 and 26 °C: about 9 % shorter for each degree warmer, rounded to 5 seconds. It is the rule NegaKit’s developing timer uses, which follows Ilford’s and Kodak’s temperature charts closely in that range. Colour processes and monobaths are not corrected.
A reused developer
Only where the maker publishes a rule for a reused developer, and then the maker’s own, with its words and a link to the sheet. A maker that is silent gets no correction: the page says so rather than borrow a percentage. Where the rule is printed for a fixed volume, we scale it to your tank in proportion, and past the maker’s stated capacity we tell you to mix fresh developer.