Profiling Printer with OCP Ink

[stratman]

If you measure the target within minutes of printing it, subsequent prints using the profile should look "correct" within minutes of printing. If they change with time, then they will no longer be correct.

The profiling process assumes that the target measurements are representative of the final print properties. Any intermediate stages are irrelevant. The profiling software has no idea what the printed target looks like straight from the printer. You should not use measurements of transient conditions for generating profiles.

This was precisely my thoughts on the subject and why deviance from it did not make sense to me.

 

[stratman]

But don't expect any prints from the Pro 9000, with OEM or OCP ink, to be unchanged in 30 years time.

How much would museum-quality glass or conservation glass (UV blocking) help in preserving the printed image?

 

[RogerB]

But don't expect any prints from the Pro 9000, with OEM or OCP ink, to be unchanged in 30 years time.

How much would museum-quality glass or conservation glass (UV blocking) help in preserving the printed image?

I wouldn't like to try to quantify this, but since the UV content is mostly responsible for the light fading, a UV-blocking glass would obviously increse print life. That assumes of course that other effects, like gas fading, haven't caused big changes too.

 

[l_d_allan]

2. I was able to return to the place where one of the test prints was made, and I was able to compare the prints to the original scene.

3. In all but the gray areas, I couldnt make any distinction between the two papers. The gray areas in the Kirkland print were a little to the magenta side of the Red River paper.

4. Before I compared the prints with the original scene, I would have said that the Red River paper was the most correct. After comparing the prints with the original scene, the Kirkland paper prints were the most accurate in the gray area.

I have some concerns whether "compare the prints to the original scene" is the best way to evaluate photo paper quality regarding color fidelity. To me, the issue is that light quality varies from day to day, and hour to hour. I find it difficult to have confidence that the original scene when the picture was taken is close enough when you return to the same scene with the print.

The same somewhat applies to test prints ... you can make prints straight from the file, and remove the variable of monitor calibration. However, you don't really know what the colors of the actual subjects really looked like.

My practice is to use several colorful paintings that my wife did of our pets, to augment the Kodak-like test files. I tried to carefully make photos of these, with a gray card and SpyderCube in the frame for white balance and exposure. When I make prints from those, I can look at both of them in an area with a north facing sliding glass door for high quality natural light. The original paintings provide a "ground truth" for what I think is a more objective comparison to the colors.

YMMV.

 

[l_d_allan]

I created this test image because it has well-defined colors:

Thanks. Added to my growing inventory of test images.

 

[Emulator]

This discussion was/is interesting but faded away without real conclusions. I am inclined toward Stratman's view and would say treat the profiling target as you intend to treat/view the print. That is, leave the profile target print to fully dry until it is stable. The intervening undried ink state is not relevant.

I picked up on these posts while looking for more on the 1315 color_test_image.png file. I was finding that the colour strips as printed were not reaching full white. The starts were darkened by a greyish haze rather than deeper colour. Banding in the mid to dark colours was noticeable in some colours but less obvious when fully dried. This description sounds as though the printer did a terrible job, but in normal use it produces excellent results. So clearly this is a stiff test. Before commenting might I suggest you try printing the file on your own printer!!

The results are all influenced by profile, intent, paper, ink and printer.

Regards Ian