I've been working on a DVD project for a couple of months now. I'm making all of the designs for the cover in illustrator after seeing the soft proofs in photoshop. If I create some raster graphics in photoshop and bring them into illustrator, will they look terrible when they're printed? What's the best way to work between the two programs?
You shouldn't have any issues.
Create a project folder that holds the AI file and a source folder for your raster TIF or PSD files.
Make sure the AI file and the source files are CMYK.
I'd suggest that you File / Place the rasters as linked resources, instead of pasting them. This way, you can update them independently in Photoshop and they will update in the Illustrator project file.
Finally, from AI you can export, save as PDF, or open the AI file directly with Photoshop to rasterize.
Just make sure every step is CMYK, since you are going to print.
I hope this points you in a generally appropriate direction.
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