Gloss differential in blacks after GO application

InkjetMall Customer Support Piezography Inks & Printing
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1

I have a 7800 set up with a Piezo2 WN-SEL inkset. Most gloss prints are done with Hahnemuhle Photo Rag Pearl, and occasionally with Fine Art Pearl. I am using the Shade 1 Opaque Photo Black. IJM made a custom curve a couple years ago for our 9800 that uses the Selenium Shade 1 Photo Black, and I’ve been using that same curve on the 7800 with Opaque Photo Black installed. I normally dry with a hairdryer for 3-5 minutes before applying GO with the GO3000 curve. Sometimes if its a big print I’ll let it sit overnight after the hair dryer step.

I’ve noticed that printing on the 7800 with PR Pearl and FA Pearl that I get gloss differential in the darkest tones of the image (the ones at 0,0,0 that are actually printing with the Shade 1 ink). I’ve tried it with other GO curves (up to 40000 units). I even applied a double coat of GO to one print and it didn’t fully cover the blacks…However if I adjust the darkest tones so they print more like 8,8,8, I don’t have the gloss differential coming though.

Since the curve was made for a different (selenium) Shade 1 ink, and this printer has the Opaque Photo Black in Shade 1, is it possible that the curve is putting down too much shade 1 ink and causing this? Maybe a custom curve would fix this?

2

Hi candela~

Do you not have this issue with the pearl papers when printing with the 9800 using SEL#1 black?
Have you tried any other gloss or semi-gloss papers with the 7800 with WN#1? If so, it it an issue on other papers as well?

Yes, I expect using a custom curve specific to the 7800 setup would likely correct for this. I reviewed your custom curves, and see we have since modified the gloss master curves to have a lower ink limit for better gloss compatibility, so I believe the combination of having a new custom curve made for the 7800 setup, and using the new gloss master curve would fix this issue.
I have attached the new P2-GLOSS-Master curve.

Please let me know if you have questions, or there’s anything else I can help you with.
Best regards~ Dana :slight_smile:

P2-x800-x880-GLOSS-Master.quad.zip (2.49 KB)

3

I didn’t have this issue with Hahnemuhle FA Pearl, Photo Rag Pearl or Cone #5 when using SEL#1 with the 9800. But I did have the same problem (using SEL#1) with Canson Baryta and Eps Exhibition Fiber (using custom curves from IJM). I was very happy with the results on Hahnemuhle and Cone papers, so I never tried to resolve why it happened with Canson and Epson papers.

I’ll send in a target for a new curve and see if that solves it.

Thanks so much,
Brad

[QUOTE=Dana-IJM;3632]Hi candela~

Do you not have this issue with the pearl papers when printing with the 9800 using SEL#1 black?
Have you tried any other gloss or semi-gloss papers with the 7800 with WN#1? If so, it it an issue on other papers as well?

Yes, I expect using a custom curve specific to the 7800 setup would likely correct for this. I reviewed your custom curves, and see we have since modified the gloss master curves to have a lower ink limit for better gloss compatibility, so I believe the combination of having a new custom curve made for the 7800 setup, and using the new gloss master curve would fix this issue.
I have attached the new P2-GLOSS-Master curve.

Please let me know if you have questions, or there’s anything else I can help you with.
Best regards~ Dana :slight_smile:

P2-x800-x880-GLOSS-Master.quad.zip (2.49 KB)[/QUOTE]

4

Thanks for the additional information. I suspect it’s a ink/paper/curve/ink limit issue, and will email you the new curve as soon as it’s complete.

Best regards~ Dana :slight_smile: