Problem with black depth in Noritsu QSS-3801 HD

[Czornyj]

While profiling a QSS-3801 HD we noticed, that the the resulting black is a bit brighter than the black on calibration strip. The native black point measured from calibration strip on both Kodak Endura Supra Premier and Fuji Crystal Archive DP2 was ~L* 4, while on a print there's only ~L* 5,7-6, with or without applied profile.

I remember that Scott Martin mentioned about Noritsu's RGB GCR, but there's no trace of halo on the edge of black from calibration strip, so it looks like RGB GCR is alredy applied there (On QSS-3201 print from Noritsu printer driver, where RGB GCR is switched off the halo is easily visible).

Does anyone know if there's a way to achieve deeper black in that printer? Noritsu service technician didn't have a clue WTF we were talking about (as I expected), so he wasn't much help.

[digitaldog]

When RGB 0/0/0 is converted through the profile, with the preferred CMM and rendering intent what's the Lstar value W/without BPC?

[Czornyj]

When RGB 0/0/0 is converted through the profile, with the preferred CMM and rendering intent what's the Lstar value W/without BPC?

In PS? It's the same in all instances and rendering intents (L* 1). In EZ Controller you can't change CMM, rendering intent (perceptual by default) nor BPC, but even when color management set to off (so the RGB numbers are left unchanged, I hope) the 0|0|0 black is brighter than the native black on calibration strip (L* 5,7 vs 4).

[Scott Martin]

When RGB 0/0/0 is converted through the profile, what are the final black values? If you made your profiles with Monaco Profiler or i1Profiler you'll often get something other than RGB 0/0/0. RGB 5/75/44 could be really unfortunate couldn't it? And that's because i1P tries to neutralize a color cast in the black point. I've already proposed an option that would allow us to keep 0/0/0 as PMP did.

The Noritsu "profiles" (which aren't ICC profiles at all) determine the aim points (think DMax values) for each paper's linearization process. Some of them have a very colorful black, especially if you're using an updated paper with the old Noritsu profile.

What paper are you using? Do you have the latest Noritsu "profiles" for that paper? You'll need the latest Noritsu profile to get a good linearization that you can build a good profile on top of. 

Also, what front end are you using? And what rendering intents do you have at your disposal with that software? (Many only allow Perceptual).

[Czornyj]

Scott, in the past I had also observed that former revisions of i1Profiler used to neutralize black of a c-print in an aggressive way, but after 1.5.0 update this tendency is almost gone. After convertion (Perceptual rendering intent) from RGB 0|0|0 I'm getting RGB 3|1|0 on Fuji Cristal Archive DP2, and 8|0|4 on Kodak Endura Premier profile, so it doesn't change the Dmin significantly.

I have the Noritsu linearization presets for Fuji DP2 and Kodak Endura Premier emultions installed on EZ-Controller. After linearization process I'm getting L* 4 on the darkest patch of the final linearization strip. My assumption was that I should get the same Dmin value on a print, but something seems to increase the native L* 4 Dmin to L* 6, even when I switch off profile convertions on a controller, so that no convertion to my custom profile, nor Noritsu generic profile takes place.

[Scott Martin]

Scott, in the past I had also observed that former revisions of i1Profiler used to neutralize black of a c-print in an aggressive way, but after 1.5.0 update this tendency is almost gone. After convertion (Perceptual rendering intent) from RGB 0|0|0 I'm getting RGB 3|1|0 on Fuji Cristal Archive DP2, and 8|0|4 on Kodak Endura Premier profile, so it doesn't change the Dmin significantly.

That's good to hear! Maybe that feedback had been heard after all...

I have the Noritsu linearization presets for Fuji DP2 and Kodak Endura Premier emultions installed on EZ-Controller. After linearization process I'm getting L* 4 on the darkest patch of the final linearization strip. My assumption was that I should get the same Dmin value on a print, but something seems to increase the native L* 4 Dmin to L* 6, even when I switch off profile convertions on a controller, so that no convertion to my custom profile, nor Noritsu generic profile takes place.

FYI, DMin refers to the minimum density that you would have at paper white. DMax is the maximum density that represent the richest, darkest black.

That interesting - I don't think I've measured the DMax on the linearization strips - I don't thing they represent what you can get through the printing pipeline though as you've discovered. There's more going on under the hood when printing images. Point is, you're profiled images hopefully have just as rich blacks as un-profiled images - or images that are color managed with real profiles on the printer.

[Czornyj]

FYI, DMin refers to the minimum density that you would have at paper white. DMax is the maximum density that represent the richest, darkest black.

That interesting - I don't think I've measured the DMax on the linearization strips - I don't thing they represent what you can get through the printing pipeline though as you've discovered. There's more going on under the hood when printing images. Point is, you're profiled images hopefully have just as rich blacks as un-profiled images - or images that are color managed with real profiles on the printer.

Dmax, of course! The higher density, the darker effect - thanks for pointing that out, I must've had worse day

This also reminds me, that I saw a "Dmax - something" function somewhere in EZ-controller menu, so maybe there's a way to tune it up...