Cyan, magenta, and black variation: the one line to remember
Inside one batch, ISO 12647-2 commonly uses ΔEab 4 for cyan, magenta, and black. That is sheet to sheet, not the 5 against the signed proof. Follow the contract version.
Inside one batch, ISO 12647-2 commonly uses ΔEab 4 for cyan, magenta, and black. That is sheet to sheet, not the 5 against the signed proof. Follow the contract version.
What this line covers
Don't use the proof deviation of 5 to pass within-batch variation, and don't put yellow's 5 onto cyan, magenta, and black. Proof deviation commonly uses ΔEab 5. Within-batch cyan, magenta, and black commonly uses 4. Both over, or only one over, are handled differently.
Side by side
| Item | Do this | Don't |
|---|---|---|
| Cyan, magenta, and black variation | Inside one batch, ISO 12647-2 commonly uses ΔEab 4 for cyan, magenta, and black. That is sheet to sheet, not the 5 against the signed proof. Follow the contract version. | Write only a feeling |
| A common miss | Don't use the proof deviation of 5 to pass within-batch variation, and don't put yellow's 5 onto cyan, magenta, and black. | Leave the wrong number standing |
| What to leave | The report must say it is within-batch variation, which two sheets were compared, the ΔEab, and the measuring conditions. A lone 4 is not enough. | Leave only a line that says pass |
Do these three first
- Confirm you are comparing two sheets of the job, not against the signed proof.
- Read cyan, magenta, and black against the common limit of 4.
- If the conditions differ, don't calculate.
