My luster prints have a lovely luster to them and they look just great to me. My only complaint about this is that I have to use the full-page setting if I have any highlights that are blown out to 255 before they will be covered with the gloss, and then I get the gloss covering the white border too. And when I use the econo mode no gloss ink is laid down on the highlights - which begs the question - if the gloss ink is supposed to cover up the white areas, when you use the econo mode why does it use any gloss ink at all? I can only assume that it does mix with all the ink no matter what, and since the blown out areas have no ink at all there is no gloss. I just ran a test and the gloss will cover up a 253 RGB area while in econo mode...
Good points. Why do you have blown-out 255 highlights? ;-)
I was curious about the GE in this respect, too, so I did some experimenting on my newly installed Z3100. I printed an image with a lot of white highlights (but also shadows and midtones), including quite a few speculars (255, 255, 255) -- yes, I've got some too! And just to make it obvious, I added a couple of all-255 circles of white on a layer.
I first printed on high gloss media (HP Instant-Dry Gloss). As you say, the GE is not applied to 255 areas but it is blended into the other inked areas. After my testing, I don't think the GE is needed in the 255 areas on gloss as the glossiness of the paper is very close to the glossiness of the inks thus making the GE unnecessary. So no problem for me there for me.
Then I moved to Satin. I printed my same image again, in both Econo Mode and Whole Page GE modes. My conclusion: Yes, if I really look hard with the light reflecting off the print surface at just the right angle, I can see the inked and non-GE-inked differences in the 255 areas (in Econo Mode; Whole Page is perfect). But honestly, this would be a non-issue for me in the real world as at every other angle of viewing the Econo GE differences in the 255 areas are invisible.
So if HP wanted to add a fourth option ("econo plus 255 non-ink areas"), I wouldn't complain!
WORKAROUND THAT YOU'VE ALREADY DISCOVERED: I discussed this GE thing with one of the HP engineers, and he gave me a workaround tip for 255 areas. In Photoshop, select (color range) and fill all the 255 areas with 254, 254, 254. Print the GE in Econo Mode and all the pure white areas now have some GE blended in, albeit with one step down in brightness. The GE this way isn't perfect, but it's better.
author, "Mastering Digital Printing, Second Edition"
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