Evaluating Black Density

Hi everyone and I hope all is well.

I’m working with a 7900 and 3880 that are both running PiezoPro. I’m printing on Arches 88 and the images feel a bit light. In other words, the lower tones seem to print lighter than what I’d expect by the numbers I measure in the files. I made a crude target that I’ll upload here and this is before a 24 hour dry down. Both printers print this file about the same.

It’s a 2.2 Gray Gamma TIF, 720 ppi, printing out of PrintTool with no color management. The nozzles look perfect on a check, and I’ve agitated the carts well. This printer has always felt a little “light” to me, but finally getting around to trying to run it down, instead of compensating with Photoshop edits. For comparison, I printed on a p800 with the Canson profile and though it’s a compressed in the deepest tones, more what I’d expect. I also notice faint highlight around the circles on the 7900. Is this a head delaminating? I’ve run alignments and should be good there.

I deeply appreciate the help and insight!

Thank you, Sean.

So, this is a linear print system so you will see the contrast ramp be = to the matte contrast (1:120 or so).

This does not mean the dMax (blackest black) is not very dark L* value. This is a different thing than what ABW or ICC printing does which blocks up the shadows to = the contrast of a normal monitor (1:200).

So take your image and adde the following photoshop curve to it:

Screenshot 2023-06-08 at 7.16.45 AM

and if you print this file it will match your screen (with the curve off).

You can burn that contrast intent right into the Piezography Pro curve with PPEv2. This is what we do at cone editions press so we can take any old file from a normal 1:200 monitor and just print it without an ICC and without modification in photoshop.


Also, you have a head alignment that you need to do (aka, your nozzles aren’t firing at the right timing) and you also need to do a PF and CR head skew adjustment. All of these things can create those hair-lines.

Also make sure you have the correct paper feed speed and platen gap.


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Hi Walker,

Understood and will give this a go! I love the openness in the shadows, wasn’t sure if I was overcompensating for it. Contrast intent makes perfect sense to me. I’ll redo the alignment too.

I’m also working on linearizing the .quad curves, I’ve started with Canson Rag for Arches, and a trying to make a 700 step target. We have an old GretagMacbeth iO table with an i1Pro. It works great with the 256 step and the configuration you included. Having a few hiccups getting it to read 700. Is there a configuration you can share for 700 steps and iO table?

I created one, and can get it to print, but haven’t been able to get the iO to read it properly. Error on my part somewhere. I’ll keep at it, and start a new thread I can’t get unstuck.

Thank you!

also make sure you are on MK on the Piezo printer! I just made this mistake on 4 targets lol.

Final dry-down L* values should be in the L*12.0 or under range for Arches 88.


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Upgraded Sean’s Target to include Percentages and more highlight patches for symmetry.

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Hi @gwieting ! Thank you for adding the percentages and posting, great idea. Walker’s curve adjustment above was perfect, and things are working well. Next up for me is getting a 700 patch target to read on our old iO table to linearize the paper curves for Arches 88.

I thought it was a great way to check curves after linearization for new papers in general. Thanks for posting your original image.

Hey guys, very nice target! Just one thing, the percentage numbers all check out, but if the others are supposed to reflect RGB numbers - I’m assuming that’s what was intended since the high numbers go to 254, they don’t match up with Photoshop readings, which is not surprising as one scale is 0 - 100% and the other 0 - 255. Unless I’m missing something, worth revising the numbers on an otherwise excellent tool to have. Thanks for sharing!

Hi @mscarbrough ! I made the original target in RGB in the Joseph Holmes, dCAM3 space. When converted to Grayscale, 2.2 Gamma the RGB numbers shift. I think that’s what you are seeing. I’ll probably update it, and I’ll post a revised when I do. Walker’s curve offset above was perfect, and the printed targets are tracking really well!

Love this discussion.

Here are a couple of 256-step targets I created a couple of years ago that might be valuable. If you can read the number, your system is resolving the difference.

First is a gamma of 2.2.

Next is a linear gamma.

Thank you @jsking ! These are very cool, will give them a go.

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I took note of mscarbrough’s observations and updated the file. I had made some fatal assumptions but now the file is accurate. I’ve deleted the incorrect file above.

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