To use the Paint panel, first select a paint tool from the Tools panel.

Opacity

For Brush and Clone strokes, the maximum amount of paint applied. For Eraser strokes, the maximum amount of paint and layer color removed.

Flow

For Brush and Clone strokes, how quickly paint is applied. For Eraser strokes, how quickly paint and layer color are removed.

Mode

How pixels in the underlying image are blended with the pixels painted on by the Brush or Clone stroke. (See Blending mode reference.)

Channels

Which channels of the layer are affected by the Brush stroke or Clone stroke. When you choose Alpha, the stroke only affects opacity, so swatches are grayscale. Painting the alpha channel with pure black has the same result as using the Eraser tool.

Duration

The duration of the paint stroke. Constant applies the stroke from the current frame to the end of the layer’s duration. Single Frame applies the stroke to the current frame only. Custom applies the stroke to the specified number of frames, beginning with the current frame. Write On applies the stroke from the current frame to the end of the layer’s duration and animates the End property of the stroke to match the motion with which the stroke was drawn.