Unexpected Fade Test Results: Ultrachrome Vs Ocp Vs Is

[costadinos]

About a year ago I placed 3 prints in direct sunlight, one was made with an Epson 7900 using Ultrachrome HDR ink, the other with an R2000 using only OCP pigment inks and the third also with the R2000, using Black and Magenta from Image Specialists and the rest of the colours from OCP.
That's more or less a year with an average of 8 hours of sunshine a day.

Oddly enough, the print made using only OCP inks looks better than the OEM! The one made using IS Black shows severe colour shift towards magenta.

Here's a scan of the three prints along with a freshly printed one (all scanned at the same time using identical exposure settings):

 

[martin0reg]

Thank you for posting, very interesting.
This test seems to be a hard one regarding the time in sunlight...

Questions:
- what paper did you used? Hopefully the same for all prints, as the paper is as important as the ink regarding fading!
- why did you mix OCP with IS? Results would be more consistent and repeatable with ink sets from ONE manufacturer.

What appears also strange to me:
- why is the OCP print less sharp than the others? All other prints are definitely more sharp and contrasty (look at the trees)! Different paper??
- Confusing: the print from OCP+IS faded to magenta (or blue?) ... take a look at the color fields: yellow and green (and also some blue tones) faded more than red tones ... magenta and dark blacks are looking good ... !? I am confused...which ink fades more, IS or OCP??

 

[jtoolman]

From my direct experience with OCP K3 inks The PK is NOT as dense and able to produce as deep a d-Max. This is clearly seen in the examples above.
The OCP magenta also has huge problems with GLOSS differential and others here ( Pharmacist ) also have found the need to replace the OCP magenta for another maker's.
I use OCP with Epson OEM PK and OEM Magentas. I buy large OEM Ultrachrome K3 carts extract the inks out of these carts for use either as a hybrid substitution to the current OCP K3 ( when using PK only ). The OCP MK is very good and I use the entire OCP K3 set with MK to print on Matte media. With good profiles the results are simply stunning. I only replace the PK and Magentas if I am printing to anything other than Matte media.
Longevity and or fade resistance I can not comment on as I have never bothered with running any such tests.

Joe

 

[costadinos]

Thank you for posting, very interesting.
This test seems to be a hard one regarding the time in sunlight...

Questions:
- what paper did you used? Hopefully the same for all prints, as the paper is as important as the ink regarding fading!
- why did you mix OCP with IS? Results would be more consistent and repeatable with ink sets from ONE manufacturer.

What appears also strange to me:
- why is the OCP print less sharp than the others? All other prints are definitely more sharp and contrasty (look at the trees)! Different paper??
- Confusing: the print from OCP+IS faded to magenta (or blue?) ... take a look at the color fields: yellow and green (and also some blue tones) faded more than red tones ... magenta and dark blacks are looking good ... !? I am confused...which ink fades more, IS or OCP??

-All prints were made using the same paper. It's the paper most of the photo album makers around here use for printing wedding albums, it's pearl 260g properly coated paper.

-The specific combination of inks (OCP + IS M/K), is because when I started using OCP inks I wasn't satisfied with the black and magenta (black was weak and magenta was a rather red hue, also weak), so I replaced the two problematic inks with those from IS. Unfortunately I never used all-IS inks, so I couldn't include a test print made with IS only.

- It looks less sharp because I applied a "Dust and scratches" filter in Photoshop in all of them, in reality they look the same sharpness-wise. The paper I used has a very rough surface and doesn't scan well, the original image was full of small white highlights.

-While the IS inks maintained a slightly better d-max, the fact that there is a strong colour shift makes them look worse. I can not tell for sure which color causes the shift, but since the same print made with OCP inks only doesn't have that, it has to be either the IS black or magenta. Look at areas of pure black, like on the staircase, this is clearly a different black (more magenta) than the original. Also, keep in mind I was using an R2000 which has a Red ink as well, so the reds should probably contain more red ink (OCP) than magenta.

 

[jtoolman]

Funny I tried getting the complete OCP ink set for the R2000 here in the USA but Rjetteck only had 6 colors minus Orange and Gloss OP ( 6 maching colors from the set for the R1800 R800 ).
I replaced the missing OCP Orange and GLOP with IS. Had to profile it to get good a color match. Seems to work fine. Will it fade faster? I really do not know but it might be interesting. I Also have the complete IS set which pretty much matches OEM in color. As well as about 15 sets of the OEM inks canibalized from the R2000s being used in the DTG industry. I really should just begin to use those instead of farting oround with hybrid ink sets.
Joe

 

[martin0reg]

...
-While the IS inks maintained a slightly better d-max, the fact that there is a strong colour shift makes them look worse. I can not tell for sure which color causes the shift, but since the same print made with OCP inks only doesn't have that, it has to be either the IS black or magenta. ...

The OCP print fades evenly on all colors, the K3 print fades slightly to blue tones, the OCP+IS fades strongly to magenta.

"Fading TO magenta": this has to be due to fading OF the yello and green tones, doesn't it ...!? My actual conclusion: on the OCP+IS print the OCP inks were fading faster than the IS inks..

edit: after double checking the color fields and the "rainbow" of the OCP+IS print and looking at a cromatic circle, I guess it must be faster fading of yellow and cyan, which causes the shift to magenta. Or other way around, slower fading of magenta..

 

[costadinos]

The OCP print fades evenly on all colors, the K3 print fades slightly to blue tones, the OCP+IS fades strongly to magenta.

"Fading TO magenta": this has to be due to fading OF the yello and green tones, doesn't it ...!? My actual conclusion: on the OCP+IS print the OCP inks were fading faster than the IS inks..

The fact that OCP inks fade evenly is probably what makes them look better than the other two, even though the individual inks probably faded as much as the other two.
What's really disappointing is the fade characteristics of the yellow OEM ink, which faded the most out of the three (look at the rainbow for instance, all hues related to yellow are completely washed out). Apart from the yellow, the OEM is the one that faded the least in my opinion.

As for the IS fading to magenta, it could be that the black ink itself turned into another colour. I don't really know if the IS black is made purely of black pigments, but if it isn't and it's actually a blend of coloured pigments designed to produce black, one of the components could cause a colour shift.

 

[RogerB]

As for the IS fading to magenta, it could be that the black ink itself turned into another colour. I don't really know if the IS black is made purely of black pigments, but if it isn't and it's actually a blend of coloured pigments designed to produce black, one of the components could cause a colour shift.

I think it is unlikely that the black ink would cause a shift in the mid-tones. Generally the black ink is only used for the very darkest tones, say the top 10%. My bet would be differential fading with the M fading less than C & Y - that would affect all the tones.
However, there are some apparent discrepancies between the OCP and the PC + IS K/M. The pure OCP shows much less fading of the of the light yellow-green patches where the M clearly would have very little influence. I'm not at all sure how to explain that one.

 

[costadinos]

I think it is unlikely that the black ink would cause a shift in the mid-tones. Generally the black ink is only used for the very darkest tones, say the top 10%. My bet would be differential fading with the M fading less than C & Y - that would affect all the tones.
However, there are some apparent discrepancies between the OCP and the PC + IS K/M. The pure OCP shows much less fading of the of the light yellow-green patches where the M clearly would have very little influence. I'm not at all sure how to explain that one.

I'm also confused with the results. But the differential fading you mention looks to be exactly what's going on with the OEM ink (the magenta hasn't faded at all, and the yellow faded a lot), yet there is no overall magenta cast.
The yellow patches of the OCP and the OCP+IS prints look very similar to the eye, when placed side by side. The IS magenta patch does seem stronger, but take a look at the right side of the rainbow and the dark areas of the staircase image, the deepest blacks do seem to have a more magenta hue when seen side by side.

In retrospect, I should probably have also printed another image in greyscale to ensure only black ink was used.

 

[ullipops]

To me it looks like it is a black or gray that turned magenta. The gray scale represented in the bottom of the picture that looks like an 'X-Rite Passport Color Checker' at least suggest this.