Gloss differential + Gloss Optimizer = Sabatier Effect?

[Some Guy]

Odd problem on very glossy paper with Epson's dye ink.  First pass I can see some gloss differential in the black tones, so I ran the print through another printer using clear piezo Gloss Optimizer (GO) to minimize the differential.

Oddly, the print now seems to be reversing in the highlights which become darker at angles.  The blacks are somewhat fixed in differential gloss with the G.O. coating, but at the expense of the highlight now.

I cannot find the term used for "highlight reversal" on inkjet paper as it doesn't strike me as "Gloss Differential," but maybe the same just now in the highlights?  Sabatier Effect on inkjet paper even possible?

More strange is the G.O. seems to have softened the image too (Now seems less sharp.) and some of the Epson dye ink has also smeared and streaked after the G.O. coating.  I also can see the wide 3880 feed roller wheels track impression in the G.O. which seems odd as I thought that grabby roller was behind the printhead, but it must be embossing the dye ink a bit and the G.O. is doing some odd banding covering the feed roller's track about 1/2" wide over the length of the print.  Print sat a day between the ink and G.O. too.  Flipped it 180 (Day 3) and the image is even softer and another 1/2" feed roller track on the opposite side of the image.  Maddening!

Don't know if more G.O. is good or not.  One coating may be all it can take if it is reacting with a prior, as well as the dye ink.  Maybe G.O. is better with only pigment ink?  Back to spray gun and Art Shield?

SG
 

[Jager]

Interesting results, SG.  I've considered using Cone's GO on Epson OEM-ink prints made with my P800, to see if that might eliminate the odd bit of gloss differential.  Haven't tried it yet.  And, of course, that would be with pigment inks, so may not be equivalent to what you're seeing with your dye inks.

The mild image softening doesn't surprise me - I'm guessing any kind of clear overcoat tends toward that result.  But the highlight reversal is indeed curious.

You were using 1400 dpi for the GO?

[Ernst Dinkla]

I think pigment inks settle better in the print and are less affected (dissolve, migrate) by a new load of ink medium.

Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
December 2014 update, 700+ inkjet media white spectral plots

[Some Guy]

....
The mild image softening doesn't surprise me - I'm guessing any kind of clear overcoat tends toward that result.  But the highlight reversal is indeed curious.

You were using 1400 dpi for the GO?

I was using QTR to apply the GO coating.  Set unidirectional at 2880 dpi and a GO coating of 15000 for each pass.  I thought 15K would be less softer than their suggested 20K-30K they normally use, but the two passes with it really softened (less sharp) the image.  I'm thinking along with Ernst that it could be mixing and maybe migrating along with the other Epson ink to diffuse it.  Seems prone to smugging with fingerprints too (They become white on the glossy part?).  I don't know if the Epson GO ink would perform any better than Cone's if I could find a machine that took a larger Epson GO cart to get some out of for the piezo 3880 GO cart.

The paper was RR Metallic Pearl and the highlight reversal was apparent on highlighted areas (Tips of nose, shoulder, elbow, etc.) of very fair skin sunlit skin outdoors which was sort of shocking in the reversal effect.  Sort of like a Daguerreotype held at an angle.  Bizzare.  I have some textured metallic (PermaJet Titanium and some Inkpress Metallic Luster) that may address the glossy reversal.  The GO overcoat may not be as prevalent on it either, or break out the spray gun gear.  Dunno.

SG