Latex 360 color consistency is not there

[ProWraps]

thank you for this. its not just me! this echos my experience to a "t".

For what it's worth, I'll share some of my experiences with these machines, and a few tentative conclusions I've reached along the way.

My first experience and the first overall impression I had of these machines is that I hate the entire idea of them taking all inking control away from the RIP and contoning them in the machine. The built in ink splits are terrible, and guarantee a grainier print than can be obtained by a properly profiled 25500/26500/260.

My second observation is that the onboard-made ICC profiles are, at best, adequate but uninspiring. They'll work for a lot of midrange work, but for anyone serious about color, they have serious black generation issues, and their perceptual rendering intent has some serious clipping issues.

And of course that's all before any color inconsistency issues.

As far as the color inconsistency goes, here's the path I've been down:

When I first saw these machines and profiled them, it was at a shop that had several, and was running Flexi-Signs.

Pretty well-known place, and they had had 26500's for years, and ran them with no issues.

First time I profiled the 360's, I did the onboard calibration, then I ran a linearization in the RIP as well, then I made the ICC profiles with a 3rd party engine and imported them in.

There were initially three machines, and because each one was a tiny bit different, and because these guys want to print across all three machines for individual projects, I profiled each one individually.

And it worked. All printed correctly, and all matched exactly. Visual test, by the way; I have a test image that has several neutral and near neutral images on it. My test is always to print it on two machines, then cut across one and overlay it on another. If there are any inconsistencies, you'll see them. Over the years I've found this to honestly be a much better indicator then measuring Delta E.

However, as soon as they did any maintenance, the machines no longer matched.

I re-profiled them, and didn't hear anymore from this particular client for awhile.

However, I have other clients with the machines, running them with other RIPs, and over time, what I came to conclude was that these machines are always applying a canned linearization, whether you ask them to or not.

And what I concluded happens is that when you do the "calibration" routine as part of media creation, the machine makes a "calibration/linearization" file that it uses until any situation happens that causes it to dump it. When it does, the front panel message changes to "obsolete", the machine reverts to its default "calibration" and of course neutrals in particular go right out the window.

Then of course you can do a "recalibration", however what you're using is a seven patch-per-color target, and an on-board spectro. Not a really robust way to do a linearization, and my experience has been that every time I do that, I'll get a different result. Probably acceptable if you aren't completely color critical; most definitely not acceptable if you are.

However in fairness I will point out that I've heard and seen that other people have gotten better results.

I have another client in Minnesota with one of these things and I was actually boarding a plane to go see him when I got a call from a guy at HP who told me that the reason for the issues my other client was having had to do with the RIP they were using. And the issue is that the 360 does not RIP in the RIP, it RIPs in the printer.

I told him I thought that was absurd, but he insisted. He also told me that the only RIP manufacturer who had figured this out and was capable of dealing with it was Caldera, and HP had a team going out to my first client's to install Caldera and resolve the issue.

That was just before the holidays, and as of yet, I don't know the resolution there.

However, I spent two days in Minnesota working with a 360, in this case driven by Onyx, and what I can say is that we did a series of tests, and they all corroborated my theory. We made profiles using the onboard linearization, then an Onyx linearization and then a 3rd party profile, and they printed perfectly.

We pulled and re-installed a printhead, the display went to "obsolete", then we reprinted the same image, and the color had changed.

We "re-calibrated" and they changed again, but not to where they had been before.

Then we made a media with no internal calibration, did an Onyx linearization and a 3rd part profile. Print was accurate and exactly the same as our first print. Then we again pulled and re-installed a printhead, again reran the image, and it did not change at all.

Both myself and the client were sure we had it. Unfortunately, this machine is still not stable. It has continued to wander around.

I'm working with the client remotely on a series of tests, but as of yet, I don't have anything entirely conclusive.

Also of note here and kind of "off the record" but I talked afterwards to a friend at Onyx, who told me that at HP, there are something akin to two armed camps: The Onyx Camp, and the Caldera Camp. And the Onyx camp is convinced Caldera is the Devil, and vice versa.

Which is kind of funny... unless you have one of these machines and you'd like to get this issue resolved.

 

[Morkel]

Thinking about OMAS. If I understand it correctly, it measures the media stepping, environmental factors, and the alignmnet of the stars or whatever, to make sure that each pass drops the ink in the best possible position to align with the previous pass. This is so that the print is visually accurate. However, it is not mathematically accurate, or even consistent. If environmental factors fluctuate, or even differences in how different saturations of colours go down, the printer will adjust its stepping inconsistently. Theoretically, turning OMAS off means that there is the potential to see slight banding between passes, but the length of the print should at least be consistent (if not fully accurate, allowing for media tolerances).

Sooooo... I have made a new media preset, "SAV tiled". I've set it up as 10 pass 110%, but CMYK only, to avoid whatever colour inconsistencies are caused by the stretched lc/lm printhead capacity. And with OMAS off. Testing it, it really shows how spoiled we are with CMYKcm, the graininess when not using the light inks is bugger-all when not looking close up, and is most noticeable in neutral tones. Something that is a worthwhile sacrifice for 10+ metre wide walls.

I've yet to test it on a real job yet, but there are a few coming up. I also plan to print some rulers beside each tile to see if there is still fluctuation. Again, when I'm done, I'll share the results.

 

[Hotspur]

OMAS

Thinking about OMAS. If I understand it correctly, it measures the media stepping, environmental factors, and the alignmnet of the stars or whatever, to make sure that each pass drops the ink in the best possible position to align with the previous pass. This is so that the print is visually accurate. However, it is not mathematically accurate, or even consistent. If environmental factors fluctuate, or even differences in how different saturations of colours go down, the printer will adjust its stepping inconsistently. Theoretically, turning OMAS off means that there is the potential to see slight banding between passes, but the length of the print should at least be consistent (if not fully accurate, allowing for media tolerances).

Yes sort of...OMAS sits under the media and takes images of the texture of your medias back surface - it expects to see the same pattern repeated further along as the media moves - if the pattern is out due to whatever reason (media expansion / contraction / environmental issues etc etc) it alters the drive on the fly to bring those two images back into alignment which gives accurate media feed pass overlaps.

But remember this is just automating what all other manufacturers make you do manually - print feed adjustment is available on all printers for the same reason and if you need to use it you are altering the final length of the print whether you do it automatically or manually. The OMAS isn't a problem that needs a solution it's just doing a job you would otherwise have to do.

The real issue is the amount of adjustment that is required due to the extra heat of a Latex - this makes any adjustment much larger on the Latex and thus any length differences much larger. The fact that it's making these adjustments automatically rather than asking the operator to do them isn't the problem - it's the size of the adjustments required that gives these effects and that's something you have to live with in a Latex due to the heat involved.

Switching off the OMAS means you will eventually get print feed adjustment issues unless you are lucky which will introduce more banding so I guess it's a compromise.

Also don't forget that OMAS predates Latex by some way - it first appeared in the Z6100 (if memory serves...) so it's been a difficult introduction eg although it flashes away in the L26/260 it was not doing anything apart from when a roll was loaded as they switched it off in a FW update and used the encoder due to multiple issues - so HP are still working to perfect it.

 

[Morkel]

Well, I'm surprised... It worked!

It wasn't the biggest wall (approx 6500 x 2600mm) but of the 5 drops there was only maybe 1-2mm maximum that some areas didn't line up perfectly, which was much better than I expected and way better than we've ever been able to achieve. Colour was also very close - in fact if there was any shift, it wasn't noticeable.

On this one we were using PhotoTex, which in itself is quite dimensionally stable, so I'll need to try a few more before I'm properly sold. But it's a good start. It was quite short though - I made a 1m x 1m grid pattern that was quite bare (thin black lines on white) on one edge, but had blocks of heavily saturated colour on the other edge, just to see if it made a difference to material stretch or printer advance. For the full metre, one edge was 991mm, the other 991.5mm. So only half a mm between them, but approx 9mm short over a metre. This translated pretty exactly to the real print - I'd put 20mm bleed top & bottom, the installers applied it to the crop marks at the top but needed 15-16mm of the bleed at the bottom. But consistency is the goal, and across each drop I got it, so we'll just have to stretch it 1% in length from now on.

 

[dypinc]

Well, I'm surprised... It worked!

Colour was also very close - in fact if there was any shift, it wasn't noticeable.

Was this using CMYKcm or CMYK?

 

[Morkel]

Was this using CMYKcm or CMYK?

CMYK only, thanks to your tip.

 

[kffernandez]

In the substrate library in the listing of media there for example under SAV is two generic medias listed. These are existing media with a calibration and profile and are junk do not use or clone these.

At the top of media list in for example the SAV library there is + New Self-Adhesive Vinyl, when you open this you have a choice of Generic Self-Adhesive Vinyl or Generic Backlit Self-Adhesive Vinyl. These do not have an old calibration or profile attached. These are the ones to use when creating new media.

hi dypinc!

I have an L310, and while it doesn't have the ability to produce profiles, it does have the capability to linearize.

All my neutrals went down the drain a few months back, and i was able to restore things to normal by producing my own profile using an old media profile, linearize it using the onboard hardware [it had an obsolete flag], used the free flexi version to ink limit + linearize, and then a third party profile maker for icc generation + black point. now, after reading this post, and realizing the importance of using a generic media setting, i'm not sure now if i used a generic media from the start, or just cloned an old one i had.

i now plan on making new profiles but would like to clarify two things:
(1) after choosing a generic media, do i need to calibrate and linearize it using the onboard hardware?
(2) will future onboard linearization be reliable now, or will it just mess up my profiles again?

any help would be greatly appreciated. thanks in advance!

kelly

 

[dypinc]

All my neutrals went down the drain a few months back, and i was able to restore things to normal by producing my own profile using an old media profile, linearize it using the onboard hardware [it had an obsolete flag],

I would not trust any media setting with a obsolete flag unless you know it was created from the new media (at the top of the list) since the latest .12 firmware. If you are going to linearize with your RIP the flag should be "Recommended"

i now plan on making new profiles but would like to clarify two things:
(1) after choosing a generic media, do i need to calibrate and linearize it using the onboard hardware?
(2) will future onboard linearization be reliable now, or will it just mess up my profiles again?

any help would be greatly appreciated. thanks in advance!

kelly

1st point. Just to clarify this again. At the top of media list in for example the SAV library there is + New Self-Adhesive Vinyl, when you open this you have a choice of Generic Self-Adhesive Vinyl or Generic Backlit Self-Adhesive Vinyl. These do not have an old calibration or profile attached. These are the ones to use when creating new media.

2nd point. Good question because I don't think anybody knows if HP will again do something in the future to mess up existing calibrations and profiles. Safest route as I see it is do RIP linearization and profile only on media that is flagged as the calibration being Recommended.

Things have slowed up enough that I have finally been testing a number of different ways to calibrate and profile media. I finally loaded a demo of ColorGate while I was doing some testing and found that its profiling leaves a lot to be desired. Gamut was lower than my profile created with Fiery Color Profiler. So I created some new media setting that do have the onboard calibration this allowed me to create a profile generated with FCP to be loaded on the printer. I could then pull this profile into ColorGate from the printer. The printed result was the same in case you were wondering.

So I tested 4 ways of doing this.

1. RIP linearization and FCP profile on non HP calibrated media (flagged Recommended). This plotted the highest gamut but only slightly over 2 and 3 method. This of course gives you the ability to re-linearize and see what difference shows up in measurements.

2. RIP linearization and FCP profile on top of HP calibrated media (flagged OK). Visually no difference but with gamut plot noted above. This also gives you the ability to re-linearize and see what difference shows up in measurements and see what affects re-calibration on the printer has.

3. HP calibration and FCP profile with RIP being able to send this profile back to the printer. Visually no difference but with gamut plot noted above. This does not give you the ability to re-linearize and see what difference shows up in measurements and you will only be able to visually see what affects re-calibration on the printer has.

4. HP calibration and profile generated on the printer. Visually more muddy look probably from lake of black controls, but gamut plot shows almost as good as above and better that a profile created with Colorgate or Onyx. Been a while since I demoed Caldera and can't say with any certainty about Caldera's profiling. Have only tried these three other RIPs with the 360. Interestingly I did bring a HP onboard profile into FCP and regenerate a profile with my preferred black generation settings. What I found was I could create a better profile but not to the quality of a profile generated with FCP.

For what it is worth. 1, 2, or 3 work fine, and visually look the same. Gamut plot wise very little difference, but it is too early to tell which in the long run is best. If HP again makes changes that invalidate the calibration and the ability to re-calibrate previous calibrated profiles then 2 and 3 would be more risky, but 2 and 3 take less time if needing to re-calibrate. For anything that is very color critical I would choose method 1, and then 3 for everyday banner vinyl etc. One note about profile black generation on the printer it does not take into account when using CMYK only and does the same black generation as when using CMYKcm. Another thing, I can't find any increase in mid tone gamut by using CMYK over CMYKcm, which I thought might be possible, especially trying to overcome the stupid low ink density HP restricted us too with 8 pass and lower. Now that we know the short comings of using just one lc/lm printhead I can see why they did it. Trouble is that does not even help when using lots of lc/lm inks. I have found using CMYKcm at 8 pass and under is kind of useless anyhow. In fact I have started using CMYKcm only when really needed and at only 12 pass and higher. Much less color inconsistencies that way.

 

[Decomurale]

color consistancy is a major issue with our new latex 360.

UPDATE: After printing with 4 litres of ink I have to say that I had serious color issues starting at about 2 litres used. My last 2 litres have been a nightmare! The thermal heads seem to be less precise after only half their recommended life span. So as it stands right now I am looking at 6 sets of heads per year instead of 3. Very frustrated. I have been reading all kinds of threads about color issues with the latex 360. I also must say that this is something I never experienced with my roland printers nor did I expect to have to deal with a new latex 360. It is still an ongoing issue for us and we have had to repeat many jobs due to panels not matching in color. All our mural jobs are multiple panel jobs. every long run has inconsistencies. I have read about power spikes in the 220 volt line, bad inks, bad firmware, bad heads etc. Bad, Bad, Bad!!! This is unacceptable in my book. We run a high end wall mural company and these issues are killing us. I am actively looking for another solution. Will keep you posted..

 

[dypinc]

You haven't mentions what media settings you are using, but it might be good to evaluate if you need to use the lc/lm inks especially if your using 10 pass or lower. Seems the use of one lc/lm printhead is a major factor in the color consistency problem.

 

[derekw13029]

So, I've read this thread several times, and fortunately I had yet to experience this issue on my Latex 330.

But today....

Flexi was doing weird things, like printing odd previously saved versions of files. So I uninstalled the previous version, re-installed Flexi 12, and updated the firmware on the L330. Uh oh.

I updated to Nexus_01_10_01.2 from Nexus_00_06_02.10

From my understanding of this thread, it was the .12 firmware that seemed to be giving the issues, so I just didn't update. But after this latest round of updates, now everything is screwed.

I came in today (Monday morning....), put in a roll of Frederix Canvas SUV, ran an image, and I swear it shifted halfway through. The skin tones and neutrals looked great at the beginning of the print, but by the end everything was WWWAYYYY pink.

So I did what this thread had recommended (I think....). I made a new profile for the canvas. I didn't let the printer do any sort of calibration on the new profile. I copied the settings manually from my previous profile that had worked (20p, 80% ink density, all other settings the same).

While my colors still aren't right, they are WAAYYY better than they were. So now I'm stuck with doing what everyone else has already had to go through, which is making new profiles for all my media.

Sorry to resurrect an old thread, but has anyone had any more issues with color continuing to change? I mean, this seemingly happened in the middle of a print, which makes me very nervous......

 

[dypinc]

I believe that the documentation for a couple of the firmware upgrades stated that there would be a run in time for color changes. This is maybe what you are seeing with that change in the middle of a print. Your passes are so high and the ink density is so low that it not likely to be ink starvation for the ONE lc/lm printhead.

Because of the firmware changes it is possible the 80% ink density on the old firmware is not the same as the new firmware and enough ink is not being laid down to be able to match the old firmware. I print Frederix Satin SUV canvas all the time and use 12pass 120% Ink density with 230 degrees. You might want to try that.

 

[derekw13029]

I will give it a shot. Making a new profile with no onboard calibration got me close enough to where I could color correct in photoshop and get the print out to the customer. I will experiment today. Just made another profile with CMYK only. Currently testing.

 

[derekw13029]

I'm just trying to think of anything that could have caused such a wild shift, if in any case it wasn't related to the firmware update.

This time, I was prompted while installing Flexi to install the desktop driver for the L330 in order to use the printer in different programs. I thought this sounded like a good idea, since I was getting weird results in Flexi all of a sudden anyway. So I installed the driver, but hadn't actually tried to print from photoshop yet. Is there any way that could be making some kind of conflict?

 

[jfiscus]

After complaining about the color consistency not being there on the 360 we had, and no one believing us... we ended up selling ours - hope it did better for them than for me! After talking with a guy from HP he confirmed that as the environmental conditions changed within the room/printer after a few prints that colors will indeed shift. The HP rep told me to run a few "waste panels" before printing the real jobs and that should clear up mid-job color shift. Good luck calibrating to that!

 

[dypinc]

After complaining about the color consistency not being there on the 360 we had, and no one believing us... we ended up selling ours - hope it did better for them than for me! After talking with a guy from HP he confirmed that as the environmental conditions changed within the room/printer after a few prints that colors will indeed shift. The HP rep told me to run a few "waste panels" before printing the real jobs and that should clear up mid-job color shift. Good luck calibrating to that!

Sorry, I always forget about mentioning this possibility because of the other printers I run I have to maintain a stable environment, and I just don't think about that others may be having wild swings in humidity and temperature.

 

[dypinc]

I'm just trying to think of anything that could have caused such a wild shift, if in any case it wasn't related to the firmware update.

This time, I was prompted while installing Flexi to install the desktop driver for the L330 in order to use the printer in different programs. I thought this sounded like a good idea, since I was getting weird results in Flexi all of a sudden anyway. So I installed the driver, but hadn't actually tried to print from photoshop yet. Is there any way that could be making some kind of conflict?

Isn't the desktop driver just a virtual printer for Flexi?

 

[Yeahgor]

I would not trust any media setting with a obsolete flag unless you know it was created from the new media (at the top of the list) since the latest .12 firmware. If you are going to linearize with your RIP the flag should be "Recommended"...

that
I'm sorry, is that you talking about? - https://support.hp.com/gb-en/document/c06559424

 

[SignLadyWeymouth]

Thanks Paul,

The bolded is exactly what we have done. When I say "generic", I mean I created a new Media from scratch, using the "+ New Self Adhesive Vinyl" and then selecting "Generic Self Adhesive Vinyl" (apologies, Polymeric was what I named the new media but the generic starting point was simply SAV). From there we went through the heat settings / ink % test (eg, 100%, 110%, 120%), then did the Colour Calibration, then made the ICC profile.

I did though copy this as the basis of the Monomeric media, but the colours were almost identical anyway and when I did a new Colour Calibration they were pretty much a perfect match. These were the first two medias that I made and, like I said, they'd worked perfectly for 9 months or so. Whenever the greys were just slightly out, a new Colour Calibration would have them spot on. It was only in December of last year that they started to go bad.

In your opinion, is it worthwhile me creating a brand new media again, putting in the same temp/speed/ink%/etc settings, and seeing if that new media prints correctly and holds its values?

Oh my word! We have had the exact same issue for the past 6 months or so!!! I have spent countless hours trying troubleshoot and trying to fix it. Between HP Support and Flexi support and nobody can seem to help with the issue. I did eventually build my own ICC profile and It absolutely helped with the pinkish purple grays but now our blues are all printing either muddy or purple. I'm ready to give up on this machine. Mine is a 370.