Colour shifts on hp z3100 (or hp z-series in general)

[FlightDeck]

Hi all,

I had been relatively confident that my color management process was working well the past couple of years, but this weekend my hp z3100 threw a curve ball at me. Here is the symptom:
- Print a photo. Then print the same photo with a wide black border added, no other adjustments. The latter print comes out darker and more saturated, particularly in the reds. (Note I'm only comparing print to print here, not trying to compare print to screen.)

Here are the details of my setup (this is a home-printing setup for photography):
- Photoshop CS5
- Printer CM OFF in hp driver
- PS manages colour using APS-produced ICC profile
- Rel Col
- **Black Point Comp ON
- hp z3100ps GP 24"
- hp Pro Satin Photo paper (yes, I know...)
- GE Full Page (same as in ICC profile)

** I'm thinking this could be the "issue". My naive expectation was that adding a feature to the image, such as the wide black border, would not cause a colour shift in the rest of the image. However now that I think about it, it does make sense that if I add a deep black border to a relatively light image, and PS is trying to shoe-horn that gamut into the printer's gamut, and with Black Point Comp turned on, that the result may be a darkening of the whole image compared to no border.

Would turning Black Point Comp OFF be the most consistent approach? In my example the image with the black border is the most faithful, while the one without looks "washed out" (so much that it led me to think that my red ink was dead, given that the red was getting low. I've since replaced the red ink, and only minor difference is noted---I recalibrated after).


An extension to this question concerns printing multiple images at once using nesting. Since I have PS controlling colour, not the printer, my expectation is that the colour of any given image will look the same regardless of what other images are nested next to it. Given the above situation with black borders inducing a noticeable shift, I now wonder about dark images and light image nested together, for example.

Any greatly insight appreciated. Experimenting with this is going to burn some paper..., but I'd like to try Black Point Comp ON and OFF, as well as nesting the same image side-by-side, one with black border, one without.

Thanks,

 

[FlightDeck]

Okay I figured it out (I guess). It appears that it was the red ink combined with not recalibrating after its replacement. I just ran test prints with and without borders, and with and without Black Point Compensation, and they all look the same to my eye (and look "correct").

If curious, here was the sequence:
- Good print (black border)
- Red ink low warning next day
- Washed-out print (no border)
- Red ink fail/replace warning; replace red ink
- Slightly less washed-out print (no border)
- Recalibrated
- Good print (border)
- Good test prints with/without border and Black Point Comp
- Good print (no border)

In my haste to leap to some complicated theory about borders affecting the results of Black Point Compensation I overlooked that I did not recalibrate immediately after the red ink replacement.

Crisis averted, life makes sense again.

Except that I am somewhat curious why the recal would have such a dramatic difference after the red ink replacement. Any ideas? Is there any guidance on how soon after an ink swap before the prints run true again? Is just a recal adequate?