Is your analogue 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 iPhone's camera and a light source. No hardware testers, no sensors to buy, no guesswork — reliably from 8s down to 1/500.
HOW IT WORKS Open your camera's film back, remove the lens, and put a light source behind it. ShuttR Check uses your iPhone'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 — ShuttR Check measures dependably from 8 seconds down to 1/500.
An iPhone 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 happens to cover where mechanical shutters drift the most and where a deviation actually shows up in your negatives. Timed speeds slower than 1s are there too, for the cameras that offer them.
WHAT YOU GET
A guided, step-by-step measurement protocol — no photography or 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, so you can track a shutter's condition over time
A camera collection to track shutter's performance including import / export function of your camera list
A shareable "shutter checked" certificate (image or PDF) — perfect for camera sellers on eBay, Etsy, or classifieds, showing buyers exactly what they're getting
SHUTTER TYPES Horizontal and vertical focal-plane shutters are tested and validated — these are the shutters in most classic SLRs and rangefinders. Leaf (central) shutters should work just as well, since the app measures the light pulse itself and doesn't care how the shutter produces it, 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 — if you need certified figures, a service technician with proper equipment is still the right call.
It also does not measure shutter capping. The app times how long light passes through, not how evenly the curtains expose across the frame. A shutter that tapers or caps at one edge can still show correct overall timing here.
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
