Stop Bath — Film Dev Timer

A timer for people who develop their own black-and-white film. Pick your film, developer and temperature, and Stop Bath lays out the whole process — pre-soak, develop, stop, fix and wash — timing each step and prompting you when to agitate. The timer covers black-and-white processes only. The negative viewer works with both black-and-white and colour negatives. TIMES FROM THE DATASHEETS Development time depends on the film, developer, dilution and temperature. Every time in Stop Bath comes from a manufacturer datasheet, and the source shown on screen opens the original document so you can check it yourself. Where no official time exists, Stop Bath does not invent one. It says so plainly and offers an external reference for further research. BUILT FOR AN ACTUAL DARKROOM • Clear current-step and remaining-time display • Agitation reminders at the right moments • Swipe between processing steps • Drag the progress bar within the current step • Full safelight-red mode • Screen stays awake while timing • Celsius and Fahrenheit support SEE THE RESULTS Photograph a negative, place the sampling box over the frame and tap Invert. Fine-tune black point, white point, gamma, contrast and red/blue balance, then save the result to Photos. The negative viewer is designed for quick inspection and selection; it does not replace a dedicated film scanner. PRIVACY Stop Bath works entirely offline: • No account or sign-in • No ads or analytics • No personal data collection • Images are processed only on your device • Photo Library access is add-only and cannot read your library English and Chinese. Designed for iPhone and iPad.