Color Shifting Panels Coming Off My 360/365

[NathanSignWorks]

Hi guys,

So I'm a print tech at a wrap company and we've been have problems with color shifts in panels for a few months now while printing wraps. I've tried everything I know of to get this issue resolved with no success. We are using Onyx 12.1 and are running a latex 360 and 365 and printing on IJ180CV3 and lamming with 8518. My designer is panelling in Illustrator and then saving to PDF. The room environment is controlled with the average temp being between 72 and 75 degrees. The humidity averages 35 to 45% I've tried running head cleanings between each print, alignments, color calibrations, and nothing works. HP sent a tech out for 3 days and he could not fix the issue. It's happening across both our Latex so we thought it might be a power issue, so we ran new power to each 220 and put them all on their own breaker in a separate box. I've asked my owner for an Eye1 so we can build our own profiles instead of using the crap that comes with the printer, but he is dragging his feet on this. Has anyone come across this, and how did you solve it?

 

[AKwrapguy]

I had read somewhere that there might be an issue with the Magenta. From what I understand basically the magenta head temperature can fluctuate causing the color difference. There is a firmware fix that is supposed to help with this.

 

[dypinc]

You are rotating every other panel aren't you?

 

[Lane J]

Is your calibration off? In the substrate menu, it should Calibration: OK or Calibration: Obsolete.

I know I've been burnt by printing something when it read Obsolete, then calibrated later and ran the same job. Same situation, it wasn't WAY off but enough to tell.

 

[Bly]

This has been discussed plenty before.

As far as my experience with this printer goes you can minimise the effect by:
Recalibration before each job.
Printing adjoining tiles in sequence.
Flipping alternate tiles.
Making sure your heads aren't too old or misfiring.

HPs thermal heads are consumables so have a limited lifespan.

 

[NathanSignWorks]

Yes, I rotate every other panel. My profile is calibrated and my heads are brand new. I run a optimize print quality cycle every morning before I start printing, and I clean the heads after every two panels. I have the latest firmware and HP even sent us new profiles that are supposed to help control the temp of the heads more effectively. I also print an ink dump before every run. Nothing has helped.

 

[NathanSignWorks]

Oh and I do print our wraps in sequence.

 

[NathanSignWorks]

I had read somewhere that there might be an issue with the Magenta. From what I understand basically the magenta head temperature can fluctuate causing the color difference. There is a firmware fix that is supposed to help with this.

I heard something like this as well. Is there a way to tell the printer to just print in cmyk and forego the lc/lm?

 

[Bly]

How bout that option in the profile that warms the heads up before it starts the job?
Long run consistency mode I think it's called.

 

[NathanSignWorks]

How bout that option in the profile that warms the heads up before it starts the job?
Long run consistency mode I think it's called.

Yep, I always run with this on. I also have tried increasing the inter-pass delay offset by 50/100/150 with no effect.

 

[dypinc]

I heard something like this as well. Is there a way to tell the printer to just print in cmyk and forego the lc/lm?

Sure, make a new entry in your preset and choose CMYK instead of CMYKcm in the Advanced settings. Then make a new output profile and your good to go. If your going to print with a lot of solids with heavy use of the light links you'll have to slow it down or run the risk of ink starvation since there is only one lc/lm printhead.

 

[NathanSignWorks]

Sure, make a new entry in your preset and choose CMYK instead of CMYKcm in the Advanced settings. Then make a new output profile and your good to go. If your going to print with a lot of solids with heavy use of the light links you'll have to slow it down or run the risk of ink starvation since there is only one lc/lm printhead.

Will give it a shot tomorrow and let you know how it works.

 

[ericm]

on the the 300's its known to cause this 1) take up and dancer bar and 2) print a dummy print to warm the machine up....
watch the videos by Timothy Mitchel

 

[Pauly]

After every panel. print this control wedge off. Then you measure them to get the LAB value of each patch. Do the same for the other control wedges. You want to find out the delta E value which is your colour difference tolerance. under 3 is good (visually < 3 you cannot see the difference when they're next to each other)
Hopefully you know how to use excel (saves buying another program)
Put your data into excel. Note you should be able to save your patch measurements with i1p and drag them into excel.

You'll need to use this formula to get the Delta E value.
√(L1-L2)²+(A1-A2)²+(B1-B2)²

E.g
A - B - C - D - E - F - G - H - I
1| Delta E L A B L A B
2|
3|

Formula: (you'd put this in A1 column in this example a2 for the next a3 and so on. You can click and drag after the first)
=SQRT((B2-E2)^2+(C2-F2)^2+(D2-G2)^2)
And you'll get your DeltaE Value.
You'll be able to see which head is shifting or if your whole printer is shifting.

But you'll need an 1i. or a spectrophotometer of some sorts.
IDEAlliance ISO 12647-7, 3-Row Digital Control Wedge 2013 | Idealliance

 

[NathanSignWorks]

After every panel. print this control wedge off. Then you measure them to get the LAB value of each patch. Do the same for the other control wedges. You want to find out the delta E value which is your colour difference tolerance. under 3 is good (visually < 3 you cannot see the difference when they're next to each other)
Hopefully you know how to use excel (saves buying another program)
Put your data into excel. Note you should be able to save your patch measurements with i1p and drag them into excel.

You'll need to use this formula to get the Delta E value.
√(L1-L2)²+(A1-A2)²+(B1-B2)²

E.g
A - B - C - D - E - F - G - H - I
1| Delta E L A B L A B
2|
3|

Formula: (you'd put this in A1 column in this example a2 for the next a3 and so on. You can click and drag after the first)
=SQRT((B2-E2)^2+(C2-F2)^2+(D2-G2)^2)
And you'll get your DeltaE Value.
You'll be able to see which head is shifting or if your whole printer is shifting.

But you'll need an 1i. or a spectrophotometer of some sorts.
IDEAlliance ISO 12647-7, 3-Row Digital Control Wedge 2013 | Idealliance

This is awesome thanks. Will give it a shot once my owner gets me a spectrophotometer. Why wouldn't HP do this when they had their latex specialist out to our shop for 3 days?

 

[Pauly]

This is awesome thanks. Will give it a shot once my owner gets me a spectrophotometer. Why wouldn't HP do this when they had their latex specialist out to our shop for 3 days?

Because this is more in the colour managing side rather than tech. Techs just know how to fix the issue. Some techs know the machine back to front but your issue there's so many variables. Most techs will will test and try different things to solve it which is costly. But most will do this. Even the techs from Oce/Canon AU which are very, very knowledgable will know a hand full of issues that will cause the same problem. Just narrowing down what is causing it with out spending much is hard.

I believe every shop needs some sort of Spectro + basic software. It really can get you out of trouble at times. create basic profiles or just measuring colours for reproducing. Onyx works hand in hand with the i1.

There is software that will get you the DeltaE value with out using excel. For example barbieri Gateway, but you need a barbieri device which are quite expensive.
There's "colour think pro" that you can upload 2 measurements and it'll automatically get you the deltaE value on all patches right away.
Not sure what Xrite can do though. But Excel is powerful if you know how to use it.