Using indesign CS5, I make a pantone solid spot colour background.
I import two of the same photos: one a greyscale circular pshop file with transparency surrounding the circle ( the file is not flattened).
The other is the same photo, but I make a clipping path around the circle and then flatten the file and save as a jpg.
Both photos are put on top of the pantone solid color background in Indesign.
I export the indesign file as pdfx 1a using pdf-presets under the file menu.
If I open the pdf in Acrobat and open the "output preview" panel and turn off the "simulate overprinting" box, the pshop photo disappears, but the jpg with the clipping path is fine. They print as they appear: one disappears (Pshop file) and one is OK: the jpg.
If you import the pdfx 1a pdf back into Indesign, you will see that the pshop image has disappeared.
I understand this happens to others not just me. is there a fix?
Does it work with all a spot colours and transparency?
If I save as a higher version of acrobat (say 7). The pdf looks fine and imports back into indesign fine.
And if I send to the RIP the RIP seems to handle it fine. But if I take that Acrobat 7 file and put on a page and export as pdx-1a, I get the same problem
Spot colors and Transparency do not play well together, but can be used together if you follow some rules.
jpg does not support transparency. If you're working within InDesign, you can, and should save as and use psd or tiff. Tiff supports transparency if toggled during the Save As dialog.
x1/a pdf does not support transparency, hence it was lost. In my environment, Press Quality PDF has never failed me, but High Quality and x4 have added benefits of Color Management.
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