About reducing and preserving spot colors in proofs

When you generate proofs, you can reduce spot colors by converting them to process color, mapping them to other spot colors, or omitting them entirely.
When you preserve or reduce spot colors in a proof, the changes that you make affect only the proof. The PDF digital master remains unchanged.

If you convert spot colors to process color, Color Combiner can simulate the hue of spot colors in a proof-including traps, knockouts, and overprints—using the standard four process colors.

When to preserve or reduce spot colors in a proof

Preserve spot colors in proofs if you want to see the spot colors in the proof and the printer supports the spot colors.

Reduce spot colors in proofs in these situations:

• The proofer supports only process color. Most proofers handle only process color. When generating a proof on these proofers, convert all spot colors to process color.

• The spot color requires special handling. Certain spot colors can be challenging to proof. Here are a few special spot colors and how to handle them:

  With This Spot Color	Handle It This Way
  Metallic and other colors that are hard to convert to process color	Omit the spot color or output it separately. For example, if the proofer uses donor sheets, omit the spot color when you generate donors for the process colors and then generate the metallic spot color as a separate donor sheet.
  Varnish	Output the spot color separately as an overlay. This is useful because varnish spot colors usually have an arbitrary color value, such as 2 percent magenta, that makes the varnish visible in the job files. If you leave the spot color in the proof, it may cover objects that you want to check. If you convert the spot color to process color, its color value changes the value of the process color.
  Die line	Omit the die spot color from the proof.
  White background on clear plastic	Omit the white spot color or output it separately. For example, with a proofer that uses donor sheets, use a white or yellow donor to make a separate separation that is not laminated together with the process colors. This is useful because the white spot color usually has an arbitrary color value, such as 10 percent magenta, that makes the spot color visible in the job files. If you leave the spot color in the proof, it may cover objects that you want to check. If you convert the spot color to process color, its color value changes the value of the process color.

• Spot colors were introduced in marks. If the marks (for example, the color bar) from the imposition plan contain spot colors that you do not want in the proof, do not output the spot colors.
• You use a late-binding workflow. Some printers prefer to preserve color information as long as possible. This means that they delay color conversion and color reduction until the proofing or final output stages. This is called a late-binding workflow because the job files are not tied to a specific output device until necessary.
  Caution: It is better to reduce spot colors during refine—not during proofing and final output—because it ensures consistency between proofs and final output and because color conversion is better in the refine process than in the proofing and final output processes. 

How to preserve or reduce spot colors in proofs

To preserve all spot colors in proofs, change a setting in the process template. See Preserving spot colors in loose page output and Preserving spot colors in imposition output.
To reduce spot colors in loose page output choose one of these two methods:

To reduce spot colors in imposition output choose one of these two methods: