Color to Alpha

Category: Processing > Color Channels

Shader Family: Texture

Output: Color

Extracts the alpha channel from a color input. If the input has no Alpha channel, the shader converts the input color to an RGBA grayscale. The returned R, G, B, and A channels will all have the same value.

NoteEven if the input color has an empty Alpha channel, the shader will use it, regardless of content. If you wish to convert the input to an Alpha channel, make sure the image is stripped of the blank Alpha channel.

Tips: Use this converter whenever you need to extract the alpha channel. For example, if you blend a surface with a transparency ramp, you can adjust the intensity of the ramp by adjusting the factor. This factor can also be animated. Values less than 1 turn black area into gray, and values over 1 change the gray to black

Name	The shader's name. Enter any name you like, or leave the default.
Color Input	Specifies the input color used to compute a grayscale intensity level.
Factor	The intensity to output. Default value is 1. Be sure to give the Factor parameter a value, otherwise the node will simply return black (no value) as output.

Render Tree Usage

You can use this node if you wish to isolate an image clip's alpha channel for use elsewhere (like driving a bump map, for example).

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