AI effect

[cseas]

Good morning folks,

I have a question regarding an effect in Illustrator that the did not translate through the RIP.

An AI file we received from a customer had a box colored in process over an embedded image, cmyk. The box was set to Opacity 90% - Hue.

When we exported a Normalized PDF, the effect is recognized. When we uploaded the PDF to the ORIS COLOR TUNER on the web, it proofed on our Epson printer correctly.

When placed in a layout in PowerLayout, it looks fine. When the layout is sent it through a Nexus Workflow to our Creo and HP printer, the effect disappeared.
It did not work. We were confused because the PDF looked fine and we were able to proof the file.

The conclusion we came to was that when rastered, this effect does not translate. (?)
Is this a correct assumption?

We were able to work around the issue by changing the mode to 90% Opacity Screen instead of Hue.

From personal experience, I believe some of the special effects in AI are geared for Web design and sometimes do not translate for printing purposes.

I know Prepress issues are like that old doctor joke.

Patient: Doc, it hurts when I do this.
Doctor: Don't do that.

But just wondering if anyone had run into this.



Any information and advise would be very helpful.

Thanks!

 

[Lukas Engqvist]

It sounds like it could be an overprint problem, or a spot colour problem. All effects in Illustrator can be printed, even if it is important to make sure that raster effects are set to the appropriate setting (300 ppi). Use the separation preview and transparency flattener to locate the problem areas.

In some cases/workflows it is best to use PDFx1a, even if PDFx4 is to be prefered since it is at a higher level abstraction and therefore better for repurposing or editing.

Also make sure your RIP is configured to handle colour management for Graphics and Images in the same way.

 

[cseas]

thanks for your reply Lukas.

yes, you are correct. we've been researching all day. we found the reason the effect did not reproduce on the plate was due to a white shape on a lower layer, used to knock-out color bars in the Layout.

it is an odd situation. any effect in the Transparency Panel in AI is still active in the generated PDF, due to it being transparent.
whatever is underneath the PDF, a white box (KO) or any other colored shape, will affect any object in the PDF that is set to a transparency. (Hue, Screen..) unless the object is on top of a non-transparent object, in AI file.

we'll just have to remember that.

 

[patrick.mendyka]

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[cseas]

it might be flattening the PDF when you prefllght in acrobat. that would resolve the problem.

thanks for your input!

 

[patrick.mendyka]

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[Stephen Marsh]

The ORIS RIP can use either it's ORIS Native RIP Engine or the Adode PDF Print Engine.

The Esko, Creo and HP RIP may use different RIP engines. Can you look to see if all the RIP's "line up" and use the same engine?

The Hue blending mode in theory should not alter saturation or luminosity.

The screen blending mode would affect (lighten) luminosity and perhaps hue and saturation as well.

I am not sure if simply changing the blend mode in this case would result in the same effect?


Stephen Marsh

 

[CHM]

Hue, Saturation, Color and Liminosity are nonseparable blend modes, and can have unexpected results when sending to a RIP.
The only thing you can do is not using these.

http://www.adobe.com/content/dam/Adobe/en/devnet/pdf/pdfs/pdf_reference_archives/blend_modes.pdf

 

[rich apollo]

I'll bet you a bag of doughnuts that the RIP driving your HP and Creo printers is using a PostScript interpreter instead of the APPE.