digital presses and vector graphics

[Chicago Press]

We are having a big frustration with digital presses and the way that some vector graphics print. As "old-timers" in this business, we are used to the way that vector graphics are rasterized at the resolution of the device (usually 2400 in the case of the filmsetters and platesetters we're used to), therefore they look much cleaner and crisper than line art that has been rasterized in Photoshop.

However, since we got a DocuColor 240 three years ago, we've seen many vector graphics that look very thickened and filled-in. We have resorted to rasterizing manually in photoshop to get an acceptable result. I figured it was this low-end device, and that it must not really be the resolution they said it was.

Now we are looking to get rid of the DocuColor and move into a higher-end digital press. However the tests sheets that we've run so far have the same problem!

I suspect that none of these devices are really the resolution the vendors say they are, because gradients are also stair-stepping. That problem was solved back in the 90s with PSL3 smooth shading and its 3,000+ levels of gray. My guess is that these devices are not really 1200 or 2400 dpi, and they can't do PSL3 smooth shading with its 3,000+ levels of gray because they don't have the resolution needed to produced that many levels of gray.

Can anyone explain what is going on? These RIPs must be doing something differently with vector graphics than RIPs for plates on press. No vendor (Xerox, EFI or Canon) has been able to explain. Does everyone out there routinely rasterize vector graphics in Photoshop for jobs going to a digital press? That seems really hard to believe.

I'd be happy to provide a sample file if anyone is interested in testing what we see here.

Tina DeJarld
Chicago Press Corporation

[fiatlux]

Just guessing here, which may likely be completely off the mark.

Were the original files created in Illustrator or InDesign and then saved as .eps at some point? I ask because the default .eps setting in Illustrator and InDesign are PS Level 2 not Level 3.

Also, if Distiller was used it has the option of creating a PDF with smooth shading "off." Whatever in the workflow is creating the PDFs may also have the option to turn smooth shading off.

As I said - just guessing.

FL

[Chicago Press]

Hi, thanks for taking this on.

You are talking about the stair stepping problem in gradients? I mentioned that as secondary evidence that these devices are not really the high resolution that the vendors say they are. The stair stepping happens even with gradients created in InDesign that are exported straight to Acrobat 6 or 7, i.e., that never go through Distiller or Illustrator.

The main concern is how thick and filled-in many detailed or small vector graphics print. Yes, most are Illustator and I tried resaving all samples making sure to choose PS Level 3. I tried one vendor's suggestion of scaling in Illustrator and not InDesign. It also happens with paths created in InDesign, not just with imported Illustrator files.

I may be wrong about lack of resolution being the culprit, but having worked with RIPs and high resolution output since the late 80s (yikes!), I expect vector graphics to print better than photoshop-rasterized line art, and that's not what we're seeing with digital presses.

An easy example to visualize is a feather. (This was from a real job). When left as vector, either imported Illustrator art or paths in InDesign, the result is almost a solid shape. So we rasterized the feather at 600 dpi in photoshop and used that in the job and the result is that you can see each individual frond of the feather in the printed output.

Tina

[kansasquaker]

Tina-

I'd love to play with some of the art you have. We routinely have the same problem on our DC252 and solve it much the same way. For what it's worth I know it's not a L2/L3 issue - that doesn't make any difference at all. Email me at kyle at kingstonprinting.com if you'd like to send us something.

[fiatlux]

Since PShop is includes a RIP, and it appears that files from it print fine - it would be interesting to use it to RIP the same file at different resolutions, say - 100, 200, 400, and 600 dpi. Print each one and see at which resolution you get the same artifacts that you do by sending the vector graphic through your workflow.
If you don't get the same artifacts then the problem may be how your RIP is processing the file rather than the output device.

The goal is to try and isolate the cause by separating the file, the RIP, and the output device from each other and then try to determine what, in each of those areas, might cause the problem.

FL

[X33]

try sending your job to the DocuColor using a PS3 driver that you like from another machine.

I think the problem is in the print driver.

also, have you tried a CREO RIP?

[Chicago Press]

Both good suggestions.

I agree, it could definitely be the RIP. I've looked at the RIPped data in it's Imageview (EFI Command Workstation 4.4.0.48), and there is a marked difference between the vector and raster there. I have PDFs of that too, using different printer screen modes (also made no difference).

Sending using a PSL3 driver: not sure how I would do this. We do not use a print driver to send files to the RIP at all. We drop PDFs into the Command Workstation Mac client.

Yes, we tried a Creo RIP in the Fuji demo room when checking out their (Xerox) higher-end devices. It made no difference. But it was hooked up only briefly, and the tech was not as familiar with it as with the EFI, so maybe there is a setting that should have been changed.

Thanks,
Tina

[X33]

- Try Command Workstation 5. Download it for free at Fiery Command WorkStation 5

- You should still try to print with a print driver, it should make a difference instead of just dropping the files into CWS.

[Chicago Press]

Can you clarify how I would print to this RIP with a print driver? No such workflow was set up with our install and it does not show up when I browse for printers. Would I make it an IP printer? Can you suggest a PSL3 driver? I would really like to try this, but I need some direction. Is there info posted somewhere? Also, can you explain how this is different than dropping PDFs? I'd like to understand what's going on.

Will Command Workstation 5 work with a DocuColor 240? We were told it would not. And if I install that just as a test, will it mess up my current installation that we are still using for production?

Thanks,
Tina

[X33]

Yes, an IP printer will be fine. You put the IP address of the Fiery and for the Print Queue you can use Hold or Print. You can get the drivers, instructions and a lot of documentation from www.xerox.com/support

I just checked on Fiery Command WorkStation 5 and the DocuColor 240 is listed as supported. Look for the link that says "Find out if your Fiery supports CWS5"