Adjust the hue and purity of the RGB primary colors (i.e. which red, green and blue they represent), while leaving uncolored (gray) pixels unchanged. In addition to preserving gray pixels, the opponency relationships between the colors are also preserved under this adjustment: If you increase the purity of the blue primary, the opponent yellow’s intensity increases to balance things out; If you twist the blue hue toward cyan, the opponent yellow is twisted toward orange.
This module is essentially a channel mixer (as in the color calibration module) but with a different interface. Even though the sliders are named “red”, “green” and “blue”, all adjustments are global and affect the overall colorimetry of the image, just like a channel mixer does.
When applied before the filmic rgb or sigmoid tone mapping modules rgb primaries can be used to make small adjustments to colorimetry. When applied after the tone mapping modules it may be used to apply creative edits such as tinting.
- red hue
- Shift red towards yellow (positive values) or magenta (negative values)
- red purity
- The purity of the red primary
- green hue
- Shift green towards cyan (positive values) or yellow (negative values)
- green purity
- The purity of the green primary
- blue hue
- Shift blue towards magenta (positive values) or cyan (negative values)
- blue purity
- The purity of the blue primary
- tint hue
- When applied after tone mapping, this control allows the gray (achromatic) parts of the image to be tinted. When applied before tone mapping, it acts like a white balance control.
- tint purity
- The purity of the tint that is applied to the image