Blacks on the Contone L300 Series?

[dypinc]

Just wonder what others are finding.

On the previous halftone addressable latex printers I could set the RIP to print 100% un-profiled black and get a really nice rich black.

On the L360 the calibration target the black is the same nice rich black. What I haven't been able to do is print that same 100% un-profiled black with the same RIP setting. Being a contone device are there any RIPs that can force the 100% black in the file to print 100% un-profiled black the same as the calibration target black.

I have done tests where I started with 100% black and added patches at 10% increments of CMY but none of them come close to the 100% black of the calibration target. This makes no difference if color management is turned on or off in the RIP. In fact the blacks are even worse looking with CM off and the 100% black is not black only. I suspect on a print job it this is not possible with the L300 series to print 100% black.

Anyone have a difference experience and can print a 100% black that looks exactly same as the black of the calibration target?

 

[P Wagner]

I am running a series of tests that should be able to answer this.

At this point, I am unsure whether there is a way to drive the printer in a Calibrated, but non-Color Managed state (with all color corrections and transforms turned off). I'll have definitive answers on this question this week.

 

[dypinc]

After I did my first set of black patch tests I set one patch as RGB 0-0-0 and used the RGB workflow in the RIP and was able to get the best black out of the RGB patch. Not 100% inkjet black like the calibration patch but better than any CMYK black.

While RGB will work with jobs I create there is no way I am going to be able to get designers that can't even bother to assign a profile to their PDF files to work in RGB. And sending RGB PDFs without assigning a profile can be a real disaster.

 

[P Wagner]

OK, the first test has been printed and measured on the Latex 360. This testing is conducted using the ONYX RIP (v 11.1.2). I am using 3M IJ180cv3.

There is no question that the color management setting defined in the RIP does affect the color output. By turning off all color management settings in the RIP, you are passing through the CMYK color recipe defined in the file directly to the printer. With CM enabled, the ICC Output profile is converting colors. Note that the CMYK build for 'Rich Black' that I am using is C80,M70,Y70,K100.

Calibration Only (CM Off)
100% K Only: L=8.84
Rich K: L=7.72
dE94 = 2.30

CM Enabled (CM On)
100% K Only: L=14.97
Rich K: L=6.85
dE94 = 8.54

When pure K (0,0,0,100) is converted by the output profile, it is mapping to a less dense black (sometimes called dusty black). The best (most dense) Black that I have measured to this point is using the rich K with CM on. Potentially an RGB Black (0,0,0) could be an improvement on this.

 

[dypinc]

But does your black printed from the RIP with Pure Hue enabled come anywhere close to the full black on the calibration target? In other words 0-0-0-100 with Pure Hue enabled match the full black in the calibration target. HP Engineer says it should and it did on the L25500 and L260 but I can't get that to happen on the L360.

 

[P Wagner]

After I did my first set of black patch tests I set one patch as RGB 0-0-0 and used the RGB workflow in the RIP and was able to get the best black out of the RGB patch. Not 100% inkjet black like the calibration patch but better than any CMYK black.

While RGB will work with jobs I create there is no way I am going to be able to get designers that can't even bother to assign a profile to their PDF files to work in RGB. And sending RGB PDFs without assigning a profile can be a real disaster.

Typically, the default color settings in the RIP will assign an embedded working space in cases where the file does not already have one. This can be risky of course, as this can change the file's colors in unpredictable ways.

 

[P Wagner]

But does your black printed from the RIP with Pure Hue enabled come anywhere close to the full black on the calibration target? In other words 0-0-0-100 with Pure Hue enabled match the full black in the calibration target. HP Engineer says it should and it did on the L25500 and L260 but I can't get that to happen on the L360.

Which Calibration are you referring to here? The on-board Color Calibration, or the RIP-based Calibration target?

 

[dypinc]

Typically, the default color settings in the RIP will assign an embedded working space in cases where the file does not already have one. This can be risky of course, as this can change the file's colors in unpredictable ways.

No I assign Adobe RGB which is what the PDF was that was generated and the conversion went from Adobe RGB to the output profile.

 

[dypinc]

Which Calibration are you referring to here? The on-board Color Calibration, or the RIP-based Calibration?

The onboard color calibration I was referring to. But now that you mention how does the RIP calibration black compare to the onboard calibration black. I need to check that on my end with the RIP calibration which I no longer use but maybe that is the missing part of the puzzle.

 

[P Wagner]

But does your black printed from the RIP with Pure Hue enabled come anywhere close to the full black on the calibration target? In other words 0-0-0-100 with Pure Hue enabled match the full black in the calibration target. HP Engineer says it should and it did on the L25500 and L260 but I can't get that to happen on the L360.

Not sure about this part.

The Black that is used in the first chart (with the ranges of ink amounts) is a rich black build. It would not do any good to make an ink load decision based on a 100 percent black only, because then when production files with rich black builds are printed, the ink is likely to be less than fully cured, and will probably result in oily and wet ink coming out of the printer.

 

[dypinc]

You seemed to be missing my point. The black on the onboard calibration target is black only. That is what I want when I send a job with 0-0-0-100 build and set the RIP (Pure Hue or Black as inkjet black) which is how I printed blacks with the L25000. Much better black that any rich black build I could run through CM on the RIP.

But the first print of my calibration target from the RIP is printing pure black like the onboard target. So maybe that is what is missing.

 

[dypinc]

Not sure about this part.

The Black that is used in the first chart (with the ranges of ink amounts) is a rich black build. It would not do any good to make an ink load decision based on a 100 percent black only, because then when production files with rich black builds are printed, the ink is likely to be less than fully cured, and will probably result in oily and wet ink coming out of the printer.

If the job has a rich black build then it will use the CM of the RIP to print. But with latex I would not call the as rich a black as pure inkjet black. Never could get rich black builds to print as nice a black as pure inkjet black.

 

[dypinc]

So far thought out the RIP calibration process I have had pure blacks. Just need to make a profile now and setting 0-0-0-100 with Black as inkjet turned on should print the same pure black as the calibration targets.

 

[P Wagner]

You seemed to be missing my point. The black on the on-board calibration target is black only. That is what I want when I send a job with 0-0-0-100 build and set the RIP (Pure Hue or Black as inkjet black) which is how I printed blacks with the L25000. Much better black that any rich black build I could run through CM on the RIP.

But the first print of my calibration target from the RIP is printing pure black like the on-board target. So maybe that is what is missing.

Color Calibration (Linearization) Targets must always be percentages of a single ink per ramp (no mixing of ink colors).

In the case of the Latex 300 series, we do not have access to the specific top % value used for single channel ink restrictions, because the printer does not share this with the user. They are instead based on the overall ink value chosen when evaluating the first chart in the profile process. The first chart that the ink load decision is based on contains rich blacks.

If you want to send pure K ink to generate your preferred black in production files, you would need to define the build using CMYK values (0,0,0,100 with Pure Hue enabled), and disable color management in the RIP. Based on post 4 in this thread, that approach might not come the closest to absolute K (L=0), but it won't be far from the best-case. Based on my testing, the dE94 in that scenario is 2.85.

 

[dypinc]

Discovered it was a setting on the RIP that was preventing pure black from printing. So with CM enabled and Black as inkjet black enabled I ran the same black patches again. Pure inkjet black from 100K only still looks better than any color managed rich black combination.

 

[Bly]

I dunno. The blacks on our 360s look black to me.

 

[dypinc]

I dunno. The blacks on our 360s look black to me.

All you need to do is compare the onboard calibration black with the black your printing to see if the color managed black looks watered down.

 

[Kiwisox]

All you need to do is compare the onboard calibration black with the black your printing to see if the color managed black looks watered down.

Hey guys been reading these forums for a few years, bought my first printer 8 months ago latex 310 i was going through the same issues, being discussed here until i decided to use the default black in my RIP SAi Flexi Print Pro
all of a sudden the black is perfect i found that files imported to my rip with CMYK 0,0,0100 was the worst a dull greyish black RGB was a lot better, but the Rip Black is my go to now.

 

[Timothy Mitchell]

dypinc is correct about how to print black with a latex 300 series printer

What you want to do is set the RIP up so that when you send black up in the file, it is set as 0/0/0/100. Black only. Then, in the RIP, go to the settings for the workflow and turn on "pure hues". In Onyx this is in the quick sets. If you set black to pure hue (or C or M or Y), that means any time you send a file over where the black is black only (it cannot have any CMY in the build or it will apply the ICC and change the composition) then it will just use the black channel for printing black. The black channel all by itself is excellent for solid blacks, a very rich black all on it's own, no CMY needed. I use it for all of my black text, any vector based black I send is sent pure hue only. See screenshot for Onyx.

Best,

T

 

[dypinc]

One word of warning though. You input profile has to match your print file. If you get jobs like I do (that no matter how much I harp on them) where the designer can't be bothered to assign the profile to the pdf and the original black was 100% only in WebCoated SWOP but you guess GRACol you now don't have 100% K only anymore.

You have to make sure your input CMKY profile is the same as the print file.