Colormunki comparison between old Colormunki Photo and newer Colormunki Photo

[pharmacist]

Today I used Calibrite CCStudio to make a profile (BW optimized method using the 1 + 2 target procedure), between my older Colormunki Photo and my newly purchased second hand Colormunki Photo (Thanks to @palombian ).

Printer: Epson SC-P800
paper: Netbit Glossy 300 gsm (Aldi Belgium)
inkset: Ocbestjet K3 (PB: mixture of 25% Ocbestjet PB + 75% OCP PB)

Please use iccview.de to upload and compare the gamut.

The scanning quality seems to be similar (take into account the reading error). I Also printed the picture twice to compare using profile one and profile two.

 

[Ink stained Fingers]

The profiles look very much identical - as close as they can be for consumer level equipment

 

[pharmacist]

I discovered the newer Colormunki seems to produce a visually darker black, despite not visible in the gamut views. Very strange. If you look at the pictures of the baby, you see the right image with the newer Colormunki has a bit darker blacks (see the image of the BW printed scenery in Venice: right image has better contrast). Both printed with perceptual content and BPC. Maybe I should print without BPC to compare with. It seems the newer Colormunki has produced a profile giving a deeper black than my older Colormunki, despite iccview saying both profiles are similar. Very strange.

 

[Ink stained Fingers]

It was about half a year ago that we discussed quite in detail issues with AgyllCMS profiles and BPC

https://www.printerknowledge.com/th...ion-gives-composite-black-when-checked.15740/

You are in a somewhat similar situation here again - understanding what the profiling software is doing and why are the results not exactly as you would expect them. One problem is that we only have a limited set of tools to go into the details.
Colorthink gives me this readout for the media blackpoint

Profile Netbit 1 Lab 10.7 0.08 -3.17
Profile Netbit 2 Lab 10.9 0.01 -3.21

That's so close together that you wouldn't see a difference.

I'm using Gamutvision now to display the B/W response for both profiles with the rel. colorimetric rendering intent, I'm overlapping the displays for both profiles

The curves overlap perfectly - except at the very left end - there is a small step down for the Netbit 2 profile, barely visible - at the cursor. The starting blackpoint values as used by Gamutvision are Dmax 1.73 vs. 1.79 (with 1.79 slightly darker) . Dmax values are not typically used in the colorimetric environment, it's a log10 density value but depending as well on the paper white point which can let comparisons become difficult. And about no other profiling related software is actively using it.

I think you are seeing these differences in your prints - I don't have an explanation why the curves look different at the dark end , it is not typical that curves with BPC on show such a kink in an otherwise smooth curve. You may redo that test with another paper to see if that happens again.

 

[Tony4597]

I discovered the newer Colormunki seems to produce a visually darker black, despite not visible in the gamut views. Very strange. If you look at the pictures of the baby, you see the right image with the newer Colormunki has a bit darker blacks (see the image of the BW printed scenery in Venice: right image has better contrast). Both printed with perceptual content and BPC. Maybe I should print without BPC to compare with. It seems the newer Colormunki has produced a profile giving a deeper black than my older Colormunki, despite iccview saying both profiles are similar. Very strange.

Comparing profiles in Colorthink Pro they are indeed very close. There is about a 2% gamut volume difference between the two. When graphically overlayed there is really nothing in it and I agree with ISF that it really should not be noticeable in print.
BPC is always on for perceptual rendering intent regardless of how you set the on off switch, so you should not see any difference.

How does relative rendering compare?

 

[pharmacist]

I just printed another picture using the two different profiles and this time it looks very similar. Same black level (visually no difference compared to the prints above). Maybe it was caused by the fact the ink particles tends to concentrate in the print head after one week no printing and need some shaking after the first print to get an even distribution of the pigment particles.

 

[Ink stained Fingers]

I was looking for some profiles I did for various pigment inks for the Netbit paper in a WF2010W printer, I got black levels in the range of L= 4 - 7 , and not L=10 as you see it with an L=10.7 or 10.9 , that's a pretty weak black level on a glossy paper. The Netbit paper does not deliver the darkest blacks overall, but I got below L=4 with the Canon PFI-105 Photo Black ink drawn from expired cartridges on the Netbit paper . The Canon PT-101 paper got me to L=3 with that ink, and some Ultrawhite glossy paper (manufacturer unkown) to L= 1.9 . An overprint with a gloss/chroma otpimizer further improved these values.

 

[Engine-Number9]

The baby in the second picture seems lighter and less "noisy" in the face. There seems to be a bit more saturation too for the other pictures in the picture.