Grayscale conversion

Last update: Thu Feb 26 2026 00:00:00 GMT+0000 (Coordinated Universal Time)

{width="200px"}

Converts a color image to grayscale by weighing the luminance of each color channel.

This node may be used as an optimised method to extract a grayscale channel out of a color image, by setting all ‘Channel weights’ values to 0 except the desired channel, which should be set to 1.

Most nodes can be set to output in either grayscale or color, where the former is preferred for simplicity and performance reasons.

Indeed, it is recommended to work in grayscale from the outset and colorize images later in your workflow, using for instance a Gradient map node.

This means that a grayscale conversion node is generally only reserved for cases where you specifically want to convert a color image to grayscale. In those cases also take a look at Grayscale conversion advanced and Color to mask.

Parameters

Input connectors

Output connectors

Examples

Parameters

Channel weights Float4

Sets the weight of each of the RGBA channels in the grayscale conversion. By default, an even split is done across the RGB channels.

Flatten alpha Boolean

Sets the behaviour of the Alpha on the final grayscale result, as grayscale values cannot contain Alpha information. When True, the grayscale conversion is multiplied against the input image’s Alpha channel

Background value Float

Sets the base background value when the input has an alpha mask. I.e., determines which pixels are to be treated as transparent. Available when ‘Flatten alpha’ is set to ‘True’.

Input connectors

Input Color PRIMARY

The color image to be processed.

Output connectors

Output Grayscale

Examples

Coming soon.

recommendation-more-help

dd48abc6-e399-43d2-9777-578ec70c5a23