Digital BW, The Print

Bob

Thanks for the results.  Do you think the common colour UC inks are the same
as the R800 inks - sounds like they are all different ie all new hi-gloss?
What's interesting is that we can use the (dull) UC inks (or their replicas)
and then improve on them re bronzing and differential with a solid glop coat
- sort of like glossing up their non-gloss ink.

I have been coating my colour and B&W prints with glop and the results are
amazing - except for the slight dulling of paper white that comes with a 50%
load (I am hoping that MIS glop 2 will be better in this regard).  The
unfortunate thing is that I prefer the finish of papers like Luster and this
finish is not the same after a glop coating - it is more glossy (surprise
surprise).  I would like to see a non-shiny coating formula that simply
evened out the reflective surface and killed bronzing with a lighter load.

Steve


> From: Bob Frost <bob@...>
> Reply-To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> Date: Mon, 7 Mar 2005 14:11:08 -0000
> To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> Subject: [Digital BW] More on Epson's use of GLOP
> 
> 
> When some of us were recently discussing Epson's use of GLOP (Gloss
> Optimiser) in the R800, Koloshor suggested that the only way to resolve the
> matter was to look at a print file and see which inks were used where.
> 
> With Roy Harrington's help, I've done that as follows.
> 
> I initially started looking at grayscales, but found it decidedly difficult
> to tell when the printer was switching from printing one patch to the next,
> because of the nature of Epson's microweave. So I made a series of 25 simple
> images, each containing a 1" square of a gray value (in increments of 10
> from 255 - 5 (and 0)). These images were all in rgb and were printed with
> Printer Color Management set in PS and ICM set in the driver, with GLOP on
> Auto, with PhotoRPM as the resolution, and Premium Glossy as the paper
> setting.
> 
> The 25 images were printed to files from Photoshop, decoded, and then output
> as txt files.
> 
> Results
> 
> Only Photoblack was used at 0/0/0 and 5/5/5, but at 15/15/15 magenta, blue,
> cyan, and yellow were used as well.
> 
> The amount of photoblack decreased steadily up to 105/105/105, and was
> absent from 115/115/115 upwards, while the amounts of magenta, blue, cyan
> and yellow increased steadily from 15/15/15 to 105/105/105. Red was not used
> anywhere.
> 
> Glop was not used until 105/105/105, where it's use overlapped with the
> disappearance of photoblack, and its use increased from then on to
> 255/255/255, while the amounts of magenta, blue, cyan, and yellow decreased
> steadily.
> 
> At 255/255/255 only GLOP was used.
> 
> Conclusions
> 
> So we can see that in the darker half of the grayscale, the glossiness of
> these inks is entirely attributable to the inks themselves, NO GLOP is used.
> While in the lighter half of the grayscale, as the glossiness of the inks
> decreases, due to reduction of ink load, the use of GLOP increases directly
> to compensate for this, until at 255/255/255 the patch is pure shiny GLOP.
> 
> A knowledgeable Epson person at the Focus on Imaging Exhibition last week
> told me that the HiGloss inks were more glossy because they had altered the
> coating on the pigment particles, and put in the pure GLOP to compensate for
> lack of ink in the lighter patches.
> 
> Bob Frost.