Color Shifting...

[kdw75]

I have an odd problem that started recently. We have a Xerox C75, with the attached Fiery, soon to be upgraded to an external unit, and it has been showing color shifts on large solids recently. We have a particular job that really showcased the problem today. It is a 13x19 inch sheet with a PMS 185 red block flooding almost the entire sheet. Then it has other artwork on top of that red block. As usual I warmed up the machine and calibrated it before the run. Then during the run it shifted to a colder red, like there was a weaker yellow. I tried recalibrating, but that didn't fix it, so then I built a complete new profile for the sheet, and that didn't even help. Finally after giving up and running the job as it was, after a few thousand the colors shifted back to more yellow like it should have been.

The way it suddenly shifted almost seems like it would be a software issue, but that is just my guess. I replaced the drums and even the fuser, just to see if it made a difference, and it did not.

Any thoughts on what this might be? Has our RIP been corrupted or does it sound like a mechanical issue?

 

[seratne]

Sounds like the nature of digital print. Large solid areas will never look press quality. Even worse when it's a screen. I'm not familiar with the C75, but we had a ColorPress 1000 that was all over the place. Our environment wasn't the best. And it had a habit of recalibrating itself during print runs and doing large color shifts. Sounds like something similar on your machine.

We had everyone out from Xerox with our struggles with the CP1000. Software people, hardware people, district managers, regional managers, everyone. We had lots of issues with the machine.. Eventually we solved the problem, by having Xerox remove it. And upgrading us to an iGen, in a new room for it with humidity, temperature, and air quality control.

As much as we put the blame on Xerox for giving us a "lemon" machine. I blame the marketing/sales people more. Digital print, even though it has been around for decades in one shape or another, is still in it's infancy. And they are overselling what their machines can do.

They're taking a simple desktop laser printer that's 1' x 1' x 1' and adding all sorts of tech and processes on top of it until it's a 6' x 10' x 20' machine. Trying their best to turn a consumer device into a production press. And to their credit they've done a great job. Most digital presses if given the correct environment and media can produce excellent results that are way above acceptable. But, once you start throwing different variables at it, the balance that they've been able to achieve becomes slightly unstable. And you wind up with color shifts, jams, etc.

What the printing industry needs is a new technology for "digital" print. Whether that's inkjet, nanography, new ways to use laser printers, or something else entirely, I'm not sure. What I am sure of is that there are people much smarter than me coming up with new ideas that will hopefully lead to some new innovative cost effective products.

 

[kdw75]

Sounds like the nature of digital print. Large solid areas will never look press quality. Even worse when it's a screen. I'm not familiar with the C75, but we had a ColorPress 1000 that was all over the place. Our environment wasn't the best. And it had a habit of recalibrating itself during print runs and doing large color shifts. Sounds like something similar on your machine.

We had everyone out from Xerox with our struggles with the CP1000. Software people, hardware people, district managers, regional managers, everyone. We had lots of issues with the machine.. Eventually we solved the problem, by having Xerox remove it. And upgrading us to an iGen, in a new room for it with humidity, temperature, and air quality control.

As much as we put the blame on Xerox for giving us a "lemon" machine. I blame the marketing/sales people more. Digital print, even though it has been around for decades in one shape or another, is still in it's infancy. And they are overselling what their machines can do.

They're taking a simple desktop laser printer that's 1' x 1' x 1' and adding all sorts of tech and processes on top of it until it's a 6' x 10' x 20' machine. Trying their best to turn a consumer device into a production press. And to their credit they've done a great job. Most digital presses if given the correct environment and media can produce excellent results that are way above acceptable. But, once you start throwing different variables at it, the balance that they've been able to achieve becomes slightly unstable. And you wind up with color shifts, jams, etc.

What the printing industry needs is a new technology for "digital" print. Whether that's inkjet, nanography, new ways to use laser printers, or something else entirely, I'm not sure. What I am sure of is that there are people much smarter than me coming up with new ideas that will hopefully lead to some new innovative cost effective products.

I understand that the technology has limitations, so I am trying not to be too picky. What I don't understand though, is the fact that calibrating didn't correct the problem, if only for a few sheets. Normally if it wanders off color, then calibration should bring it back to it's baseline.

 

[Craig]

Did you power down the C75 and power it back up? On the 8000 series it will do an auto adjust by running a series of patches internally. It might do the same for you.

 

[kdw75]

Did you power down the C75 and power it back up? On the 8000 series it will do an auto adjust by running a series of patches internally. It might do the same for you.

I will hold out judgement, but it seems like this may have fixed it. Very odd. We have been running it pretty hard this week. I have put 65K 13x19 sheets through it in the past 4 days. lol Maybe it needed a nap.