can one make light magenta and ligh cayn by diluting magenta and cyan

Ink stained Fingers said:

..
..and an overcoat, in this case the gloss optimizer , very much reduces the UV/ozone effect which I cannot separate in such test. ..

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Very interesting, I wouldn't have expected such results by using GLO..

- which GLO did you use, OEM or 3rd party like ocp?
- I assume it has to be a second printing, not just ONE print with checked GLO option...
How exactly do you "overprint"? With a special cartridge setup or just an "empty" print..?..what kind of file for overprinting.. blank text page or "white" photo?
I just have reanimated an old R800 and would like to try the coating.

I was running this test on a R265 with a CISS using this or that ink, and I have another cartridge set for a quick test of other inks. I filled the black one with GO, from OCP, set the driver to normal paper, fine, gray scale printing to prevent other inks mixed in. I printed the color bars with the 'UV resistant ink' with the CISS, changed over the cartridges and overprinted the color bars partially in a 2nd pass, half of the print with GO, I simply used a uniform 'black' image. This overprinting is not very practical for normal printing, but it was a test to verify how detrimental this glossy paper is to the UV stability, the fading
is much stronger than on normal copy paper , I was surprised by this result although Henry Wilhelm, and as well statements from Image Engineering very clearly confirm that effect. I did not test any other photo paper so far, and cannot in the next time since that there is now other ink in the cartridges.
I may do some more testing in a few months with more sun, UV and ozone outside. This is just a quick test where I cannot separate the effects of UV and ozone but allows me to identify an ink which is more stable than the current dyes

Ink stained Fingers said:

...it was a test to verify how detrimental this glossy paper is to the UV stability, the fading
is much stronger than on normal copy paper , I was surprised by this result although Henry Wilhelm, and as well statements from Image Engineering very clearly confirm that effect.
...
...but allows me to identify an ink which is more stable than the current dyes

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I can hardly believe that glossy photo paper, even if it is cheap cast coated sort of, fades stronger than plain paper... if this is true, then the cheap ink jet paper (120g matte) which I use a lot and expected to fade stronger than glossy (as I have remarked on my first quick fading test with the "desert lamp" , see post #42) - could also turn out to fade lesser... will definitly keep track of this subject...

o.k., plain paper starts off with less color saturation than glossy paper, and the black ist not that black as on glossy either, I'm folding half of the plain paper with the color bars to the back, and just let the front part sitting in the sun, or no sun whatever, and when I'm checking for changes I just fold the bottom half straight and can directly compare, and dye inks on plain paper in 4 weeks fade less than this particular glossy paper in one week, that part without GO. In case of doubt I keep another like copy in the dark as a reference. That's what H Wilhelm was saying all along, and as well Image Engineering, and I didn#t really believe it until now. With one important reservation at this time - I did this test with one type of glossy paper only, cheap, instant dry. I therefore don't know whether other glossy papers have addtional coatings to prevent that effect, at least I don't see paper companies advertising this particularly. So that could be another type of test, not to compare inks but to compare typical photo papers. I could imagine that companies offering those DryLab printers - dye inkjet - Fuji, Epson , do something in this respect with the papers they are offering for these machines optimizing the longevity of the printouts. This adds another dimension to the fading questions - OEM papers or 3rd party papers for DryLab printers - e.g. Tecco is offering such papers as well. The attached image shows the fading about 2 days after I looked to it the first time and made my comments here, the fading continues - the black is gone by now - so much for a 'UV resistant ink' .

Any time I have tried to improve the longevity of dye inks in any of my fade tests they all failed as one would expect they would, dye ink just can’t be exposed to sunlight and expect to survive with or without GLOP overprinting on them.

Well that’s the results that I got when printed on both gloss and copy papers..

Yes, dye inks fade sooner or later, I just try to find a combination of inks and paper which gives me the rel. optimum in this respect, but before I start using OEM material I rather print with pigment inks.

I did another test, I used several types of glossy photo paper, Tecco, HP, Sihl, Labelheaven and plain paper for comparison, and printed CMYK color bars with a set of OCP dye inks. I folded them halfway and exposed all of them to the current springtime sun, not very strong, and there is most likely not so much ozone yet. The black bar starts visibly fading on all papers, the least on plain paper, there is at this time not much difference visible between the different paper brands, and the fading of the C and M bars start to become visible as well but less than the black bar, and this only after 5 days. The OCP ink appears to fade somewhat less than the US 'UV resistant ink' as reported above but still cannot be called 'UV resistant' at all.

Some more prints after 7 days under the desert bulb. Scanned side by side with an unexposed copy.

- dye ink on cheap matte inkjet paper 110g

- dye ink on cheap glossy photo paper 230g


(edit) printed with an epson r800, filled with a dye ink set from coralgraph, one of the few cheap dye inks for the r800...
Both papers are only cast coated, not resin coated.
The thin inkjet paper seems to fade more than the glossy photo paper.

Next time the fuji drylab ink will be in test again.
I just ordered another terrarium bulb with more UVb output.

Well, I tested some more - inks and papers . I tested one ink set - OCP dye for R265 - on various glossy papers . cheap Labelheaven - Sihl/Aldi - HP Premium Plus, Tecco Drylab Glossy - plain paper - black starts fading at about the same time on all papers, faster than on plain paper. And this within a few days in spring sunshine. And I saw another effect on some other paper which I did not recognize before, probably because one would not expect that with dye inks - bronzing. Yes, I see bronzing with OCP dye inks on particular semiglossy/silk/lustre papers almost much as with pigment inks - bronze colored changes in reflecting light. The effect is not visible at all on all glossy papers tested above, for sure not visible on matt papers. And this effect is not at all visible with some other inks tested in this cycle - e.g. Coralgraph from Octoinkjet, and a 'UV resistant' ink from U.S. O.k., that ink does not show a bronzing effect on silk papers but showed up as the fastest fading ink in my collection. The bronzing becomes visible on dark colors - dark green - dark red - violett etc - all those colors in the bottom part of the gamut pyramide. That US black is actually my 'fast fade' reference black, you almost can watch it turning brown on glossy paper....it actually may be a formula for a secret ink eliminating a printout after a few days at ambient conditions.
I did not measure the gamut of the various inks under test at this time, I try to find a 'working' ink set for me in respect to fading, and once that is identified I'll run profiles on the papers
I'm typically using with those inks.

I have now started a fading test of Canon OEM CLI-8 ink on Canon PP101 270 gsm paper and Sihl Glossy 280 gsm paper. I used an iP4300 with a brand new print head for these prints.

I also test IS ink for CLI-x21 on the same papers. I used an MP540 for these prints. The extended nozzle check for this printer is perfect.

I use the bug zapper lamp mentioned in post #43 for the test. I will check the prints after a week and compare them to prints made with the same inks and papers but kept in the dark.

I intended to compare OEM and IS inks for CLI-8 but at the present print heads in my other 5 cartridge PGI-5/CLI-8 printers suffer from clogging due to some ink growth.