Standardizing image quality usually involves a few steps in the Application Color Settings ( for starters ). You mention certain files being "washed out", but not all of them. Applying transparency can reduce color intensity ( obviously ). The artifacts you see could be what is sometimes referred to as "stitching". So, there are many variables that could be affecting your PDF. Sometimes standardizing includes selecting the proper PDF settings, which in the case of your file, would include live transparency in the PDF. Another thing to consider. Are the artifacts showing up in the proof? In some rare cases, you might see some artifacts in the preview image, but the file itself prints fine. You also should make sure in your original Ai file that your raster effects resolution setting is setup appropriately. And, when creating a PDF; there may be some compression being aspplied which could produce unwanted artifacts. Double check: 1.) your application color settings, 2.) raster effect resolution in Ai, 3.) your PDF settings in IND.
in addition to John's comment:
EPS doesn't ever contain layers with variable transparency (besides ordinary
transparency in areas, where no objects are placed).
Exporting AI files as EPS results in flattening. This is not generally wrong,
but it should be done deliberately.
For your workflow it's probably recommended to use AI files in ID.
A very different question is then, whether the ID file should be flattenened,
exporting as PDF. In my opinion it's recommended, because the result can
be checked by you. Flattening at RIP level may cause shifts which are not
under your control.
I'm aware of the cheap advice 'if your printer is not able to handle Adobe files
with live transparency correctly, the find a better one'.
By the way: I'm using regularly EPS for graphics which are programmed
directly in the programming language PostScript.
Best regards --Gernot Hoffmann
- Use and place into InDesign only native files (Illustrator and Photoshop).
- If you need to use CMYK, use the same CMYK profile everywhere, from start to end. If you know which printing condition is your final aim, use this CMYK profile an don't use any other. Set that kind of CMYK as a CMYK profile in your colour settings al allong the Adobe software.
- Do the same if possible with RGB profiles.
- Don't flatten transparencies if you don't need to do that AND if you need, do it as late as possible in the workflow. In your case that seems to be the print-ready PDF creation.
- To create that PDFs, try to use the PDF/X flavour that best suits your printing aim. Use the CMYK you set all along your work or, best, that final CMYK MUST be your CMYK all along the workflow.
In brief: Stay colour-coherent in your workflow, avoid EPS, avoid unneeded colour conversions, avoid flattening as much as possible.