All transfer curves have five color channels: C, M, Y, K, and a default spot ink. The default spot ink curve is used for undefined spot inks. You can add a custom spot ink and define the spot ink curve.

  1. In the Transfer Curve Properties dialog box, in the Spot Inks section, click the Add button .
  2. Double-click the Color column and choose a suitable color (for visual recognition only).
  3. Click the Name column and enter the name of the spot ink.
  4. Click OK.
    A curve channel is added for the spot ink. 
  5. Click the Transfer Curves icon  to adjust the spot ink curve.

  6. Click Spot and use the Spot Ink control to select the specific spot ink.

  7. You can click Transfer Curves to display the transfer curve graph and see the result of you adjustments. You can also select the Enable Editing check box to edit your curve in the Transfer Curves dialog box. In the example below, the left window shows the deviation values/curves and the right window shows the absolute values/curves. The yellow curve is the original curve, the black curve is the edited curve.
  8. Click Apply.