G7 - Questions with the trappings

Recently used the G7-2013 Paper Calculator M1, I put the white paper and had the following results according to the posted image.

I did a test print and the results were as follows:

Type Paper: Paper and Board Food Packaging
KBA105 Universal
Inks: Flint - Novavit
Ink sequence: KCMY
Reading: M1
Device: SpectroDens - TECHKON

Paper (L = 92.0) _ (a = 0.55) _ (b = 3.00)

Cyan (L = 54.0) _ (a = -35.2) _ (b = -45.00)

Magenta: (L = 45.0) _ (a = 71.0) _ (b = 1.2)

Yellow (L = 87.0) _ (a = -3.1) _ (b = 91.3)

Black (L = 16.2) _ (a = 0.1) _ (b = 1.3)

Red (L = 43.1) _ (a = 63.4) _ (b = 46.4)

Green: (L = 46.3) _ (a = -63.5) _ (b = 25.7)

Blue: (L = 23.2) _ (a = 16.8) _ (b = -40.6)

C + M + Y (L = 22.7) _ (a = 0.8) _ (b = 3.4)

C + M + Y + K (L = 10,5) _ (a = 1.1) _ (b = 5.8)

I realized that the (C + M + Y) and (C + M + Y + K) are very yellowed, how is this possible if the trappings (red and green) are not yellow on the new targets specified in the calculator?

This is normal?

How can I solve this problem?
 

Attachments

  • photo5255.jpg
    photo5255.jpg
    152 KB · Views: 209
  • photo5256.jpg
    photo5256.jpg
    315.4 KB · Views: 240
I don't have a ton of experience with the calculator so I can't tell you why the CMY, CMYK patches would be changing differently than the overprints.

Looking at your numbers though I'm curious why you started with GRACoL when the paper white is closer to SWOP (CRPC5)? It's my understanding that the paper calculator works better when you start closer to your target numbers. SWOP paper white is only 3.05 ∆E while GRACoL is 7.36 ∆E from your paper color.
 
I did not use the SWOP (CRP C5) because the value of black is very low (L = 19) for the standard here in Brazil, most clients like more saturated colors, especially black (L < 14).
Just read the manual calculator, I saw the calculator works best with smaller differences 3:00 ΔE, between the white of the ICC and the white of the paper used.
Now I was left with more doubts.
Thanks a lot for the help.
Have a great day.
 
Last edited:
I did not use the SWOP (CRP C5) because the value of black is very low (L = 19) for the standard here in Brazil, most clients like more saturated colors, especially black (L => 14).
Just read the manual calculator, I saw the calculator works best with smaller differences 3:00 ΔE, between the white of the ICC and the white of the paper used.
Now I was left with more doubts.
Thanks a lot for the help.
Have a great day.

Hi from Brazil.
So did u try another ink sequence?

http://the-print-guide.blogspot.com.br/2009/07/ink-sequence-4c-process-beyond.html
 

PressWise

A 30-day Fix for Managed Chaos

As any print professional knows, printing can be managed chaos. Software that solves multiple problems and provides measurable and monetizable value has a direct impact on the bottom-line.

“We reduced order entry costs by about 40%.” Significant savings in a shop that turns about 500 jobs a month.


Learn how…….

   
Back
Top