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Sampling White and Black Points

The Grade node lets you define white and black points by sampling pixels from a Viewer frame.

To Define Tonal Range with the Grade Node

1.   Click Color > Grade to insert a Grade node at the appropriate place in your script.
2.   Connect a Viewer to the output of the Grade node so you can see the effect of your changes.
3.   In the Grade properties panel, use the channels dropdown menu to select the channels you wish to process.
4.   Click the blackpoint parameter’s color swatch.

The eye dropper icon appears.

5.   In the Viewer, press Ctrl/Cmd+Shift while clicking on the pixel you want to define as the black point (typically the darkest pixel).
6.   Click the whitepoint parameter’s color swatch. The eye dropper icon appears.
7.   In the Viewer, press Ctrl/Cmd+Shift while clicking on the pixel you want to define as the white point (typically the lightest pixel).