You can define values to clamp minimum and maximum luminance values using the clip and reference sliders.

To clamp minimum and maximum luminance values:

1. Indicate whether this is the initial or final primary grade:
   • To work on the initial primary colour grade, click Input.
   • To make final adjustments to the primary colour grade, click Output.
2. Modify the clip and reference values using the following sliders.

   Black ClipDetermines the extent to which values will be smoothed out in the shadows.

   Black ReferenceDefines the range of values in the shadows where the Black Clip will be effective.

   White Clip Determines the extent to which values will be smoothed out in the highlights.

   White ReferenceDefines the range of values in the highlights where the White Clip will be effective.