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18% grey
Where 18% grey sits, per log.
What it does
Checks that a shot is well exposed with an 18% grey card: where the card should sit on the waveform, for each camera curve, and how to read a waveform.
How
- Pick your camera’s gamma (log curve) in the list: the value to aim for, in IRE (and the 10-bit code).
- The drawing shows a test scene (black, grey and white cards) and its waveform with that curve. Try the exposure to see the waveform move.
- On set: film the grey card, open your waveform or false colors, and adjust until the card sits at that value.
How to read a waveform
- Each column of the image becomes a column of dots, in the same place from left to right.
- The brighter a part of the image, the higher its dots: 0 IRE is video black, 100 IRE video white.
- Film an 18% grey card and set the exposure until it sits on the line of your curve (the orange band allows a third of a stop).
- Above 100, highlights clip and lose their detail; in log, the white card stays well below 100, that is normal.
Free, no account, nothing is sent: it runs in your browser, even offline.
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