Photoshop Native (PSD)
Historically, the native PSD (Photoshop document) format has been used solely for working files in Photoshop. Copies of those working files were flattened and saved in TIFF or EPS formats for placement in a page-layout program. While PageMaker allowed placement of native Photoshop files (yes, really—although it did not honor transparency), QuarkXPress required TIFF or EPS instead. Old habits die hard, and thus TIFF and EPS have long been the standard of the industry.
However, Illustrator, InDesign, and QuarkXPress 7 and 8 can take advantage of the layers and transparency in Photoshop native files, eliminating the need to go back through two generations of an image to make corrections to an original file. The working image and the finished file are the same file. QuarkXPress 6.5 allows the placement of native PSDs but does not recognize transparency. QuarkXPress 7.0 and 8, however, honor transparency in layered, native Photoshop files.
Transparency Tip
Although Illustrator, InDesign, and QuarkXPress (version 7 and above) accept and correctly handle opacity settings in a placed Photoshop native file, they do not correctly handle blending modes in a Photoshop file. The most common example is a drop shadow created in Photoshop. While the shadow will correctly darken image content beneath it in Photoshop, it will knock out of content beneath it in InDesign or Illustrator. The result is an anemic and unrealistic gray shadow—not what you want. There are some workarounds for InDesign detailed in Chapter Eleven, “InDesign CS4 Production Tips,” but a simple solution is to omit the shadow in Photoshop, and generate it instead in InDesign or Illustrator, whose shadows behave correctly, darkening content beneath the shadows as you intended.