Hello
I just print a new limiter image for calibrate Photopolymer gravure I used the P2-NU-HDPK-MASTER and the P2-NU-HDPK-HahnFAPearl curves , the problem is the shadows are not linear I got darker values on the midtones than on the shadows, I dont know if the curves I used are not optimized for UV blocking, What curve should I use for UV light blocking on Piezography 2 HDPK inks?
Thank you
Moises
You need to use an MK curve not PK. Like I said, use the Hahnemuhle Photo Rag curve. Use MK ink.
-Walker
Walker For use Matte ink do I need to change something on the setup or only selecting the UHD curve?
Thank you
Moises
just the curve and switch your printer to MK for the first test, back to PK if you need to, all the best,
Walker
Walker
Done! I printed the limiter file using the Hahnemuhle Photo Rag 308 curve and matte inks, now my print is to dark on the shadows I need to limit around 131 step, see attachment.
Sounds logical?
Thank you
Moises
Yep. Limit to 131 and curve-tune the highlights a lot darker. Then print the next target.
-Walker
Sorry for butting in here since I have no gravure experience, but I couldn’t help but notice something that may (or may not) be relevant.
Walker said:
just the curve and switch your printer to MK for the first test, back to PK if you need to
But Moises’s picture indicates he is using P2:
Keith
That is a good question Keith !
Moises
Ok Walker, but how I curve-tune the highlights a lot darker 
Did you use this curve from the Curves-HD > 3800-3880-P2 folder, with MK active:
P2-NU-UHD-HahnPhoRag308.quad
If you did switch the printer into PK mode, I’m fairly sure there would be a problem.
Keith
Hi Keith
Yes I used the curve from that folder.
For now I have printed a new target using the limit density to 129 steps and adjusting the highlights with the tweaking curve contrast, and selecting the MATTE INK option and I just got a very nice negative for start the linearization, when I tried to use the P2-SEL-UHD-HahnPhoRag308.quad with PHOTO INK I got a very very dark and grainy print.
See both targets here…
Moises Levy
Walker I’m curious about why selecting photo ink in a Matte curve the print is so Mate, and when I select photo ink with the same Matte curve I got a more glossy negative (positive)?
Best
Moises
I actually think there is something wrong with your permissions and that you are only printing the K channel (be it PK or MK) because of that. It should not be that dark on the paper or film.
Re-install quadtoneRIP to fix permissions then try again.
Also, if you are using a P2 UHD curve, have your printer set to PK, and have nothing in the PK channel but PiezoFlush than this will print very light. But not that light across the board unless you permissions are somehow messed up.
So again, re-install QTR and try again.
-Walker
