I am currently using Illustrator CS 5.1 and am having an issue with my PDF files. I have a graphic that I am building and when I import an image, place a clipping mask around it and then add a drop shadow to it, everything works fine and looks exactly as I want it on screen. However, when I save the document as a pdf, a hazy white line appears around the edges of the image. However, the line is not on the clipping mask itself, instead it is on the square edges of the unmasked version of the image. So when I have 10 masked items on the page with drop shadows, I'm getting 10 faint white squares around each of the images which looks terrible. Has anyone else experienced this? Any recommendations/solutions?
Thanks in advance!
This may actually be an Acrobat question, as I just realised that it only occurs when I convert the pdf to an optimized pdf in Acrobat. The raw pdf saved from Illustrator is clean. I will check my optimize settings and see if there's anything that seems like it may be the culprit.
I was actually hoping to find a resolution that didn't require changing preferences in Reader because this is going to be posted as a web download and I can't exprect users to know to change settings in their reader preferences. However, I was able to somewhat resolve the issue. Rather than saving the file as an Optimized PDF in Acrobat, I chose to save it as a reduced size PDF instead and the lines did not show up. I don't have as much control when saving the file this way, but it does convert it to an acceptable file size and quality. When I do that, I receive a message that states, "The PDF document contained image masks that were not downsampled". I'm assuming this might have to do with the issue that is causing the white lines.
I will try your Transparency Flattener recommendation and see if that takes care of it.