G7 - Solids Are Good - Overprints Are Not

[Bill W]

Just measured the press pieces, here are the numbers:

CM:
Target:
CV 74.6%
PB 75.8%
Bearer:
CV 74.3%
PB 85.6%

CY:
Target:
CV 80.1%
PB 89.1%
Bearer:
CV 76.5%
PB 90.6%

MY:
Target:
CV 75%
PB 79.8%
Bearer:
CV 76%
PB 85%

For those that did not see earlier definition for CV and PB - CV is initial run, no curve (1=1, 5=5, 10=10, etc) and PB is run with gray balance curve applied.

 

[meddington]

Those trap values don't look bad to me...but then again, I don't think your Lab values are too shabby either. If you wanted to improve your secondaries, you could adjust primary densities, using the individual delta a* & b* values (from your secondaries) as a guide. From the data presented, you're near the point of diminishing returns though.

 

[Bill W]

I have always been satisfied when comparing proofs created from my profiles against proofs created using the GRACol profile, taking the difference between flexo and offset in to account.

I am challenged as to how precise to be in meeting ISO12647-2 since my G7 travels have all been by the seat of my pants. I have to say thanks to all like Mike and Rich and Mark Mazur who have helped me keep my pants from falling down, but I have never received IDEAlliance feedback since we are not officially G7 certified.

In conversations yesterday, it appears that the flexo world kind of glosses over meeting secondaries numbers as our process is dry trapping not wet trapping. We can somewhat control trapping by insuring that the pH and viscosity of the ink is correct and on my press tests I make sure an ink company tech is on site to insure compliance.

So for now I will keep insuring the primaries are as close to the spec and let the secondaries be what they are.

Thanks to all that took time to be involved in this thread.