Where 18% grey and clip actually fall on the waveform — for your exact camera, log profile and ISO, with on-set calibration. Free to use.
Manufacturer
Camera
Log profile
ISO
⚠ On ARRI cameras, changing EI shifts the LogC encode — grey, clip and black IRE values change at each EI setting. Reference values here are for base EI 800 only. Use ARRI's LogC LUT Generator for other EI values.
Measure an 18% grey card at a known aperture on a calibrated waveform monitor with an incident meter. Enter the grey IRE, clip IRE, and the T-stop you used — the tool draws aperture markers on the scale showing where grey falls at every adjacent T-stop at constant incident light.