Argyll B&W Profiling

[nertog]

Hello, nertog, I used the test.ti in your attachment, then printed it, and generated a black and white configuration file. Then I printed with the black and white configuration file generated by argyll, and compared it with the configuration file printing generated by I1 studio. , I prefer the configuration file of i1 studio, which feels closer to the color of the original image, while the configuration file generated by argull looks greenish to my eyes when printed

I had a quick look at the attached ICC profile. Your black level is very high (L=26, should be 5-10 on a decent paper). The black ink seems to be very brownish, as well. If you do wish to use this specific printer-ink-paper combo, I would not expect nice b&w performance...even after profiling.

Also, keep in mind that Argyll (and other profiling packages) assume you view your images under a D50 spectrum. The light spectrum has a huge impact on dye inks, much less on pigments.

 

[VISDATA]

I had a quick look at the attached ICC profile. Your black level is very high (L=26, should be 5-10 on a decent paper). The black ink seems to be very brownish, as well. If you do wish to use this specific printer-ink-paper combo, I would not expect nice b&w performance...even after profiling.

Also, keep in mind that Argyll (and other profiling packages) assume you view your images under a D50 spectrum. The light spectrum has a huge impact on dye inks, much less on pigments.

Thank you so much, thank you for your advice. It seems that I need to replace the black ink. I would like to know what software you use to check the black level of the ICC profile.

 

[VISDATA]

Thank you for your reply. I used to use EPSON P600. The black and white one was very good. However, due to the clogged nozzle, the machine broke during cleaning. The L800 was a product I purchased in 2013. The quality was very good. Because of the problem with the nozzle of the P600 , so I re-purchased the L805 to print with pigment ink. It seems that it is really difficult for a 6-color machine to achieve good black and white.

I'm only reading this thread on the side since I'm not using ArgyllCMS for profiling nor do I focus much on the specifics of B/W printing, but I nevertheless have some questions.
@VISDATA restarted this thread with posting #3 , I don't see any comment which printer is actually the one which should be profiled for B/W printing- and on which type of paper. There is only a reference to a L805 and L801 in the personal data, the L805 is a 6 color dye ink printer - without a gray. I see principal limitations to get very good B/W prints with such a dye ink set. B/W prints may look good enough for most users - but you won't be able to get away with hue shifts of the blacks and grays under different light conditions, and it would get more complicated if your paper carries optical brighteners which cause a different paper white point if your viewing light carries some UV - like from halogen bulbs or small neon tubes.
It's a pity that the L805 driver does not support the adanced B/W mode of other higher end Epson printers which could help to get away with a greenish cast instead of trying to profile the printer.

 

[Ink stained Fingers]

It seems that it is really difficult for a 6-color machine to achieve good black and white.

It's the missing gray which limits good B/W performance, Epson is supporting a dye gray only since recently with the ET-8550 printer. the light inks are not relevant for the B/W performance. Canon is using a dye gray already since a long time on the Pro 100/200 printers - for a good reason.

I tested as well pigment inks on a L805 and an L1800 but the typical issues of bronzing and gloss differentials cannot be compensated, the effects are very much dependant on the paper/inkset combination so I changed back to dye inks on the L805.
I cannot comment on your ArgyllCMS issues, I just would recommend you to test some other than glossy papers - like silk - satin - semiglossy which can give you an overall better look of B/W prints, but as in most cases - every ink/paper combination by different manufacturers will look diffferent even if the papers are called the same - like silk.

 

[nertog]

It's the missing gray which limits good B/W performance.

Well, I have different experiences.:

* For the lighter tones, it's mainly the linearization (= hardware calibration) of the printer and inks (wildly different density or color tint). This can, to a certain degree, be corrected with a decent profile.
* For darker tones, your black ink is very important. Many black inks are far from neutral and this non-neutrality cannot be corrected through ICC-profiling. Most black dyes become more transparent in the far-red spectral regions as well, which means you get severe metameric failure issues when moving from e.g. daylight to incandescent light.

Of course, the addition of one or more grey inks makes the while linearization procedure more robust and the whole system less sensitive to small changes (ink density, tint, printhead variations, etc...)

 

[Ink stained Fingers]

Yes, light dye inks are not a fix to all B/W problems.

Most black dyes become more transparent in the far-red spectral regions as well, which means you get severe metameric failure issues when moving from e.g. daylight to incandescent light.

That's one of the problems, let me show you how bad this far-red region can be

what would you expect from a perfect neutral gray print - technically neutral, the visual impession can be different.
Analog film photographers in the past had a gray card for exposure adjustment and help with contrast control in the darkroom.
When you scan the spectral response of such a gray card you get this



That's pretty much a flat response for a medium gray at L= 47, and such a gray will look gray still at other ambient light conditions than D50.

I profiled an L1800 longer time ago , a printer w/o a light gray, and I get such a gray under these conditions for a L=46 gray



That's technically a neutral gray as well - at D50 - but this gray will look pretty much different under all other light conditions. The bulge at the far-red end of the spectrum is significant.

 

[nertog]

View attachment 15589

That's technically a neutral gray as well - at D50 - but this gray will look pretty much different under all other light conditions. The bulge at the far-red end of the spectrum is significant.

Nice illustration! Carbon black pigments have a much flatter reflectance spectrum. I suppose other grey inks are simply diluted black dyes with similar spectral issues? Have you ever checked your ET8550?

 

[Ink stained Fingers]

Have you ever checked your ET8550?

No, but I know it would be pretty insteresting to have a look to the spectral composition of grays created with different types of inksets - with or w/o a gray ink - dye or pigment inks - light or dark grays and the actual black of an inkset, and this on different printers, but I'm currently not planning to do those tests although it was on a list already since a long time since I was running an P400 and alike.

 

[Ink stained Fingers]

I found one more spectral scan - with the P400 - a pigment ink printer w/o a light gray ink - the image is incomplete - it does not show the Lab data of that scan anymore but it belongs to the same sequence of test prints as above from those days




It is not a flat curve like the Pentax gray card above but the strong increase at the red side of the spectrum of the L1800 is gone and the spectral response is much more evenly distributed. And it might even look better with a light gray ink available. This shows a tremendous benefit of pigment inks over dye inks when it comes to B/W printing . But this comment does not answer any other question around B/W printing like profiling - which rendering intent for printing - black point compensation and more and does not fix or answer any of those - I'll leave that to the B/W printing fans.