Channel > Calculations effect

The Calculations effect combines the channels of one image with the channels of another. Use this effect to quickly and easily produce some of the same results as you get from the Shift Channels effect, the Compound Arithmetic effect, and precomposing.


Original layers (left and center) and with effect applied to arch layer with Input Channel set to Gray, Second Source set to cloud layer, and Invert Second Layer selected (right)

Adjust the following controls for the Calculations effect:

Input Channel

Specifies the channel to extract and blend with the original layer. RGBA displays all channels normally. Gray shows the luminance of the original RGBA image. Red, Green, Blue, or Alpha converts all channels to the value of the specified channel.

Invert Input

Inverts the layer before the effect extracts the specified channel information.

Second Layer

Specifies the layer with which Calculations blends the original layer.

Second Layer Channel

Specifies the channel to be blended with the input channels.

Second Layer Opacity

Specifies the transparency of the second layer.

Invert Second Layer

Inverts the second layer before the effect extracts the specified channel information and calculates the blend.

Stretch Second Layer to Fit

Stretches the second layer's edges to the original layer's edges before blending. If you don't select this control, the Calculations effect centers the second source layer in the original layer and crops it to fit the effect layer's boundaries.

Blending Mode

Specifies the blend mode used for the blend of the original layer and second layer.

Preserve Transparency

Ensures that the effect layer's alpha channel is not modified.