After the shoot · Developing & darkroom
Reciprocity
Reciprocity failure compensation calculator: adjust long exposures per film stock, with 28 film curves built in.
When it helps
- reciprocity
- reciprocity failure
- reciprocity law
- long exposure compensation
- bulb mode
- very long exposure
- long exposure on film
- exposure compensation
At a glance
| Where to find it | Tools tab → Reciprocity |
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| Category | After the shoot · Developing & darkroom |
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| Platforms | iOS / Android / HarmonyOS (native) (coming soon) |
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“Reciprocity” is one of the 37 photography tools in Optaxis. Coming to iOS, Android and HarmonyOS (native) at the same time, expected between late December 2026 and early January 2027; once live, search for “光轴” (Optaxis) in your app store to download.
Optaxis