Darkroom Companion

Darkroom Companion is a clean, modern timer and time database for home black-and-white film development. No account, no ads, no tracking — it works fully offline. Whether you're developing your first roll or your thousandth, it keeps the whole process in one place. KEY FEATURES • Multi-step process timer — developer, stop bath, fixer, wash, wetting agent — with rhythmic agitation cues (sound + haptics) and a night (red) mode for the darkroom. • Development time calculator — automatically adjusts for temperature and push/pull (±stops). • Recipe database — built-in development times for popular films and developers (Ilford, Kodak, Foma, Adox, Bergger, Kentmere, Rollei), compiled from manufacturer datasheets. Add and edit your own recipes too. • Dilution calculator — get exact concentrate and water amounts from your tank volume and ratio (1+9, stock, and more). • Reciprocity calculator — correct long exposure times for reciprocity failure. • Chemical inventory — track mixing date, shelf life and capacity, with a warning before you use expired or exhausted chemistry. • Development log — keep a history of every roll you develop. • Backup & restore — export and import your data via file or clipboard. Everything stays on your device. • Available in English and Czech, with °C / °F units. PRIVACY FIRST The app collects no personal data and needs no internet connection to work. Your recipes, chemistry and history never leave your device. A NOTE ON TIMES Built-in times are indicative defaults from publicly published manufacturer data and are marked "verify". Always check against the current datasheet before real use — emulsions and batches vary.