InDesign PDFs and transparent objects on gradients

[Paul_Dieterman@adobeforums.com]

I have some InDesign files with a lot of transparent RGB PSD images on top of CMYK gradient fills. When I export these files to PDF (1.3 or 1.4) they show up fine on screen, but on printing from Acrobat 6.02 to our Xerox 790 it results in color shifts in the transparent part of the PSD's. I only can get it to work properly when I print as image in Acrobat and not as postscript. Also the postscript/distiller route works fine. Is this a structural problem with PDFs directly exported from InDesign? I know the workarounds with rasterized gradients, but that's not an option here. I'm using InDesign CS 3.01, transparency flattening high resolution, blend space CMYK.

Cheers
Paul

[Bob_Levine]

Mixing RGB and CMYK along with transparency is asking for trouble.

Bob

[Paul_Dieterman@adobeforums.com]

But it still distills fine Bob... I have to convince some designers that they can produce press-ready PDFs directly from InDesign and not through the postscript/distiller route (they will happily grab every opportunity to stay put with product X....)

Cheers
Paul

[Bob_Levine]

It's still an improper (IMO, anyway) workflow. You're going to get very
inconsitant results that way.

You can try playing around with color management and transparency
flattening in Acrobat, but I would stongly suggest simply using CMYK
images instead.

Bob

[Scott_Falkner@adobeforums.com]

would stongly suggest simply using CMYK images instead.




Don't they teach you that on day one?

[Paul_Dieterman@adobeforums.com]

I already was afraid that in the end it would finally mean batching a lot of Photoshop files. I have no experience with this printer, and for the simple reason this is a pilot InDesign project for our company, I don't want to take any changes. I know I could always send InDesign files but that's the last thing I want to do.

Thanks
Paul

[Bob_Levine]

If you don't want to take any chances then convert them to CMYK. Then,
if you're using an up to date printer, export as PDF 1.4.

Bob

[Bob_Levine]

> Don't they teach you that on day one?

They should.

Bob

[Paul_Dieterman@adobeforums.com]

Don't they teach you that on day one?




That's a little bit too easy, I think. Regarding conversion from rgb to cmyk, I'm not discussing whether or not to do it, but when. Right now I choose to convert upon export to pdf. Normally this works perfectly, but in this particular case (transparent image on gradient fill) I get trouble. Right now I even don't know if pre-conversion to cmyk will solve the problem - maybe InDesign has a problem with transparent images on gradients when exporting to pdf? Unfortunately I can not test this till next monday. To be continued...
Thanks for the input guys.
Cheers
Paul

[Lauren_Gerry@adobeforums.com]

Not sure if this is the same problem but I created a 1 page ad in InDesignCS on Windows XP in CMYK mode with grayscale tif pictures. The ad contained a gradient then a grayscale image with an alpha transparency path on top of it. I exported it as PDF and sent it FTP to my printer. The printer called and told me when opening the pdf the photos frame (picture box) instead of being transparent and showing the gradient, contained a white background. I viewed the PDF on my screen in Acrobat 6 Pro and it was fine. I noticed on another ocassion that after exporting a pdf under the same conditions that remniants of picture box frames were visable on the gradient in the background, although there were actually no boarders on the boxes themselves.

I repeated the PDF process and sent it again but unfortunately with the same results. I side steped the problem by just exporting as eps and that worked fine however this is a problem that in the future I will need to know how to fix. Is it me or is there a problem with exporting gradients and pictures together out of InDesign?

I know there is a lot to comprehend here but if anyone is intrested in what I am talking about email me and I will send the pdfs so you can see the problem.

Thank you
Lauren
com

[Bob_Levine]

What version of Acrobat is the printer using? This is indicative of
using Acrobat 4 to open PDFs with transparency.

Another possibility is the printer is placing the PDF in Quark, which
will also flatten the PDF.

Bob

[TheDoltinator]

On Fri, 27 Aug 2004 08:11:48 -0700, com
wrote:
 



seeing a lot of these "whote boxes" or white backgrounds posts on
different forums. I've seen it too in my own work. Have seen no
solutions either. If you do find what causes it, please report here.
thank you.

[Lauren_Gerry@adobeforums.com]

I am not sure what version of Acrobat they use. I know they don't have the Creative Suite and I thought that could be an issue. I only deal with this printer once a month for a one page layout. Next month I will get more information about their software.

Another printer I sent a pdf to that was acting funny is at the press now and will be shipped within a week. I will let everyone know the results when I receive it. This instance the pdf showed artifacts of picture frames that did not belong. However the printer said the pdf was good. It will be interesting to see if it was just a screen problem or if the artifacts will actually print!

Lauren

[Paul_Dieterman@adobeforums.com]

Update: converting the RGB PSD's to CMYK does not solve the problem, the color shifts remain. It must be something in the way overprint instructions are set (and differ from Distiller)in exported PDF's.

Cheers
Paul

[Paul_Dieterman@adobeforums.com]

....and there also lies the solution. I had to explicitly check "simulate overprint" in the advanced printing settings (I figured it would simulate overprint by default) and the ugly colors are gone. I guess this problem is something simular to the transparency on spots problem. You can spend hours and hours with it and in the end you just have to tick some stupid box. Oh well...

Cheers
Paul

[Bob_Levine]

Simulate overprint is for soft proofing only. You should never use for
files that will be printed.

Bob

[Paul_Dieterman@adobeforums.com]

I know Bob, and this is for in-house proofing. Please don't confuse it with the "simulate overprint" box in the InDesign PDF export settings. This is a setting in the Acrobat advanced printing settings for this particular device.

Cheers
Paul