Photoshop

Edit a spot channel to add or remove color

  1. Select the spot channel in the Channels palette.
  2. Use a painting or editing tool to paint in the image. Paint with black to add more spot color at 100% opacity; paint with gray to add spot color with lower opacity.
    Note: Unlike the Solidity option in the Spot Channel Options dialog box, the Opacity option in the painting or editing tool’s options determines the actual density of ink used in the printed output.