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Techead42
12-02-2008, 12:45 AM
I've got a customer printing a file on a CS650 that has a 3" x 6" gray bordered text box in the center of the page. Banding is occuring at the start and end of this text box alone. The rest of the page looks great (mostly black text, though the heading is Green). The border of this text box is the only gray on the image, and it surrounds black text on white background. The banding starts at the gray text box and passes along the interior text, but doesn't actually impact the text within...you can see the banding stop at each character.

Normal color prints look fantastic.

I replaced the black drum, and the banding cleared up somewhat but is still there. The banding looks Transfer Belt related, but the rest of the colors aren't affected. This occurs whether printing through the Creo controller or importing as PDF independent of the Creo. I took this file and printed it on a CS620 in the office (w piggy-back controller), and the image printed fine.

Any thoughts???

copytechman
12-02-2008, 03:11 AM
Which way is the banding occuring? From front to back of machine or in the paper movement direction? Had a C550 give me (real bad) intermittent banding front to back magenta only, found an arc point on the yellow iu of all things and the konica rep also changed out the mfp board. I found front to rear arcing on the lower end machines (C250 series) caused by bad drum grounds to the front frame where the iu sits pressed up against it with a single spring.
Regards!
A.

Techead42
12-02-2008, 03:18 AM
Which way is the banding occuring? From front to back of machine or in the paper movement direction? Had a C550 give me (real bad) intermittent banding front to back magenta only, found an arc point on the yellow iu of all things and the konica rep also changed out the mfp board. I found front to rear arcing on the lower end machines (C250 series) caused by bad drum grounds to the front frame where the iu sits pressed up against it with a single spring.
Regards!
A.

Thanks for your reply...the banding occurs in paper direction. Now that I think of it, the the entire process unit 'hangs' a bit when attempting to secure it...though this problem didn't occur until a different tech inadvertently 'introduced' this while troubleshooting a different issue...I was doing follow-up on his previous call. I can see how arcing could cause image issues, but how would this cause banding only within the confines of a gray-bordered text box? The banding is not lead to trail over the entire image, it's only on this gray text box...very strange.
Thanks again!

copytechman
12-02-2008, 03:22 AM
Hmmm, no problem, lead to rear, does it do it on an internal grayscale test prints too? Particularily in a shade @ or near the same as the box? Or any other halftone colours for that matter?
Regards!
A.

Techead42
12-02-2008, 03:25 AM
Hmmm, no problem, lead to rear, does it do it on an internal grayscale test prints too? Particularily in a shade @ or near the same as the box? Or any other halftone colours for that matter?
Regards!
A.

I'll be returning to the site tomorrow or Wed...I'd run full density test mode 53, but hadn't run it at a closer shade to the text box...thanks for the reminder...will post results tomorrow night.

Techead42
12-02-2008, 03:30 AM
I'll be returning to the site tomorrow or Wed...I'd run full density test mode 53, but hadn't run it at a closer shade to the text box...thanks for the reminder...will post results tomorrow night.

I keep coming back to the fact that while this text box border is gray, it surrounds normal black text which is on white background; in other words, the gray does not extend beyond the surrounding border...and yet the banding starts at the border, flows over the white background withough actually impacting the text (it comes right up to each character, then continues after the character)...it then flows right up to the bottom of the gray border and stops at the edge...it almost sounds as if it's something in the source file itself, but the file prints fine on the CS620 in our showroom.

Aaarrgghh.....

copytechman
12-02-2008, 03:36 AM
What kind of file is this, I've seen weird artifacts in files as well. In one case I had a customer in a print shop that kept getting these weird lines/moires in photoshop file if I remember correctly... I had him "tilt" the suspect picture a little, problem solved, was on a fiery e710 @ the time.
Regards!
A.

Techead42
12-02-2008, 03:39 AM
What kind of file is this, I've seen weird artifacts in files as well. In one case I had a customer in a print shop that kept getting these weird lines/moires in photoshop file if I remember correctly... I had him "tilt" the suspect picture a little, problem solved, was on a fiery e710 @ the time.
Regards!
A.

I'm pretty sure it was created in Quark...I wish I knew a lot more about file structures...I did have my customer print it both through the Creo and then import it as a PDF independant of the Creo, with the same results.

Techead42
12-02-2008, 03:40 AM
I'm pretty sure it was created in Quark...I wish I knew a lot more about file structures...I did have my customer print it both through the Creo and then import it as a PDF independant of the Creo, with the same results.

I may see if they can create a file w/comparable gray text box, see if they're able to duplicate this on a separate file.

copytechman
12-02-2008, 03:57 AM
Makes sense to me, quark can actual "adjust" the halftone screen of any colour, its worth a shot to try it with the same "shade" but different dpi's or screens.
Regards.
A!

Techead42
12-02-2008, 04:25 AM
Makes sense to me, quark can actual "adjust" the halftone screen of any colour, its worth a shot to try it with the same "shade" but different dpi's or screens.
Regards.
A!

You've been a big help, thanks for your input...any idea where I might find some resources on file structures (Quark, PDF, etc)?

copytechman
12-02-2008, 04:47 AM
Not offhand, sorry! You may want to try googling it though.. That may bring up some useful info!
Regards!
A!

konisolver
12-02-2008, 11:04 PM
If it has the Creo is it on Version 2? If so there is a patch to correct the gray box. I believe it is the RIP patch.

Juxta5
12-03-2008, 03:02 AM
It certainly can be a software to RIP problem. In a nutshell Quark is Adobe's competition. Adobe would not let Quark use their PDF distiller plug-in so Quark has to use OmniPage's distiller. PDF's are postscript and your CREO is postscript as well, but we've found some conflicts with Quark's postscript language, including grayscale. The best way to avoid this is to make sure that all the postscript/PDF settings are the same from the software, to the PDF distiller, to the RIP because the RIP should override the software's settings, but it is not. That might also explain why the same file will print okay at a different location, because a different RIP/printer may have a different set of default settings.

First try outputting the file at 600 dpi, 85 lpi; then try 300 dpi, 60 lpi settings. If your lines are due to a software/RIP conflict the lower resolution will eliminate them. You will compromise quality but at least you will have your answer. We've also had luck changing the screen's value by +/- 5% in the original file. The RIP's postscript printer driver simply ends up printing a different dot array and everything looks fine.

Techead42
12-03-2008, 01:07 PM
Thanks for all your input...I replaced the black main charge unit and the issue went away...you would think a faulty mc unit would cause banding across the board, lead to trail (which it typically would); this was isolated to this half-tone text box alone. Strange.

copytechman
12-03-2008, 05:38 PM
I have seen that before on image units as they get older and weaker in general, the gray "banding" lead to trail first usually shows itself in halftones.
A dead giveaway for an image unit thats going to need to be replaced soon (and pulling the charge cleaning wand doesn't help)
Regards!
A.

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