# Silverlog Reciprocity — Film Long Exposure Calculator

> Film Long Exposure Calculator (iPhone/iPad app by Simon Westgate.)

- Source: https://appshunter.io/ios/app/silverlog-reciprocity/id6756740671 (this page in markdown: same URL + `.md`)
- Developer: [Simon Westgate](https://appshunter.io/developer/1856537803)
- Category: Photo & Video, Utilities
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 15.1 · 27 MB
- Languages: American English
- Released: 2026-03-29
- Data updated: 2026-05-17
- User reviews in markdown: https://appshunter.io/ios/app/silverlog-reciprocity/id6756740671/reviews.md

## What is Silverlog Reciprocity?

Silverlog Reciprocity calculates corrected exposure times for long exposures on film, compensating for reciprocity failure — the point where film loses sensitivity during extended exposures.

HOW IT WORKS
Select your film stock from a comprehensive database covering Kodak, Ilford, Fujifilm, Fomapan, CineStill, Lomography and more. Enter your metered exposure time and instantly see the compensated time you should actually use.

Every calculation uses manufacturer-published reciprocity data or established empirical formulas, with full source transparency so you know exactly where the numbers come from.

FEATURES
• Extensive film stock database with reciprocity data
• Instant calculation — no submit buttons, results update live
• Source transparency — see the formula or data behind every result
• Works offline — no internet connection needed
• Clean, focused interface designed for use in the field
• Dark mode support

BUILT FOR PHOTOGRAPHERS
Whether you're shooting Velvia at sunset, Tri-X under moonlight, or Delta 3200 in a cathedral, Silverlog Reciprocity gives you the corrected time without fumbling with charts or guesswork.

Part of the Silverlog photography toolkit. No account required. No data collected.

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Absolute Hero | $4.99 | one-time |
| Actual Saint | $29.99 | one-time |
| Guardian Angel | $9.99 | one-time |
| Legend | $2.99 | one-time |
| Nice One | $0.99 | one-time |



## Version history (last 1 release)

### 1.0 — 2026-03-29

No release notes.

## More apps by Simon Westgate

- [Silverlog](https://appshunter.io/ios/app/silverlog/id6755815649)
- [Silverlog Mix](https://appshunter.io/ios/app/silverlog-mix/id6756785829)
- [Silverlog DoF](https://appshunter.io/ios/app/silverlog-dof/id6756788185)
- [Silverlog Hyperfocal](https://appshunter.io/ios/app/silverlog-hyperfocal/id6756801107)
- [Silverlog Flash](https://appshunter.io/ios/app/silverlog-flash/id6757318928)

All apps by Simon Westgate: https://appshunter.io/developer/1856537803

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-05-17.*