ShuttR: Shutter Speed Tester

Christian Hämmerle

About this app

Is your vintage camera's shutter still accurate — or has it drifted after decades of use?

ShuttR Check measures the real shutter speeds of your analog camera using nothing but your phone's camera and a light source. No hardware testers, no sensors to buy, no guesswork — reliably from 8s down to 1/500.

REQUIRES 240 FPS SLOW MOTION
ShuttR Check times the shutter at 240 frames per second. Your phone's main camera must support 240 fps slow motion through Android's camera API — the app checks this on first launch and tells you if your phone can't. Tested on: Google Pixel 8a.

HOW IT WORKS
Open your camera's film back, remove the lens, and put a light source behind it. ShuttR Check uses your phone's high-speed camera to measure exactly how long each shutter release lets light through, then tells you how far that is from the speed you dialled in — in fractions of a stop.

The app walks you through every step. There is nothing to configure, nothing to interpret: set up, release the shutter, read the result.

RELIABLE FROM 8s TO 1/500 — AND NOT BEYOND
This is the honest boundary of the app: ShuttR Check measures dependably from 8 seconds down to 1/500. Faster speeds are deliberately not offered. A phone alone cannot resolve 1/1000 and up with an accuracy worth trusting, and we'd rather leave those speeds out than hand you numbers that look precise but aren't. That range also covers where mechanical shutters drift the most and where a deviation actually shows up in your negatives.

WHAT YOU GET
• A guided, step-by-step measurement protocol — no technical background needed
• Automatic calibration (checks your room is dark enough and free of flickering light)
• Every speed compared against its nominal value, with the deviation in stops and a clear OK / deviation / defective verdict
• A history per camera and a service log, so you can track a shutter's condition over time
• A shareable "shutter checked" certificate (image or PDF) — perfect for camera sellers, showing buyers exactly what they're getting
• Backup export compatible with ShuttR Check on iPhone

SHUTTER TYPES
Horizontal and vertical focal-plane shutters are tested and validated — the shutters in most classic SLRs and rangefinders. Leaf (central) shutters should work just as well, since the app measures the light pulse itself, but they haven't been through the same validation, so treat those readings as unconfirmed.

WHAT THIS APP IS NOT
ShuttR Check gives you dependable, repeatable information about how far your shutter speeds have drifted. It does not replace a calibrated measuring instrument, and the results are not a laboratory reference.

It also does not measure shutter capping. The app times how long light passes through, not how evenly the curtains expose across the frame.

PRIVATE BY DESIGN
No account. No data collection. No internet connection required. Everything — your cameras, your measurements — stays on your device.

WHO IT'S FOR
• Film photographers who want to know if their gear is actually accurate
• Camera collectors curious about a new find
• Sellers who want to offer buyers real proof of a working shutter

What’s new

First Release Version 1.0