Live Metering
Full-screen camera view
Meter with a live preview, expand to a full-screen view, and lock the exposure once framing looks right.
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Film reciprocity,
ReciproMeter
Film reciprocity,
measured cleanly.
ReciproMeter is a privacy-first iPhone app for film photographers. Meter scenes with your camera, lock the reading, apply reciprocity correction, and keep long-exposure timing close at hand.
$9.99 paid app
iPhone-only v1
Privacy-first metering
No photos captured or saved
What it does
Reads live exposure metadata from the iPhone camera, calculates a base shutter speed for your chosen aperture and film ISO, then applies film reciprocity correction where needed.
Built for film
Includes official datasheet-backed film profiles, plus clearly separated community and experimental tiers when manufacturers stop short.
Reciprocity
Official data first
Uses manufacturer formulas and tables where available, with transparency when long-exposure guidance becomes community-derived or experimental.
Workflow
Metering ISO override
Override box speed when rating film differently, then carry the corrected time straight into the built-in bulb timer.
Film Library
Built-in film library
Browse built-in films with official, community, and experimental reciprocity data states where appropriate.
Screens
A closer look at the app
These are the same iPhone screenshots being prepared for the App Store listing.
Privacy
Camera metadata only
ReciproMeter asks for camera access so it can read live exposure metadata such as ISO, shutter speed, and aperture. It does not capture or upload your photos, and it does not require an account.
Release
Launching on the App Store
ReciproMeter is being prepared for App Store release as a paid iPhone app priced at $9.99. This site hosts the support and privacy pages required for submission.