Part 4. Converting Files

Task

  1. How to Save Files in Other Formats

  2. How to Optimize Color Files for Printing

  3. How to Move Files from Mac to Windows

  4. How to Build GIF Files for the Web

  5. How to Optimize GIF Color Sets

  6. How to Create a GIF Transparency

  7. How to Build JPEG Files for the Web

  8. How to Optimize Files with Variable Compression

The tasks in this part walk you through the various processes for saving, converting, and optimizing files. Knowing how to convert files is important; you don't have to work in graphics very long before someone calls to tell you that they can't read the file you just sent them. There are lots of different file formats, ranging from TIFF, JPEG, and EPS down to the obscure formats, such as Amiga HAM and Scitex CT.

File formats have evolved over time in an environment where there were no standards. Therefore, many files are compatible; you'll find that TIFF, PICT, BMP, and other formats are interchangeable as far as pragmatic functionality is concerned. Some systems require specific formats (such as Amiga and Scitex), so you can easily figure out when to employ those options.

Adding to this confusion is the discrepancy between Macintosh and Windows platforms, as well as issues with transferring files between Windows 95, Windows 98, and Windows NT. With all these different systems and platforms, it's a wonder anything gets transferred successfully.

In addition to pure file conversions, it is also important to optimize files for use in different capacities, such as prepping files for print or building compact Web files. Optimizing files involves striking a balance between image clarity, proper color modes, and file size.

Fortunately, Photoshop excels in the realm of file conversion. Before it was an image editing program, Photoshop's core technology was in file conversion. That's why there are almost 20 file formats available in the Photoshop Save As dialog box. For optimization, you will find the same optimize capabilities in both Photoshop 7 and ImageReady 7. Choosing File, Save for Web in Photoshop opens a comparison dialog box that delivers the same kind of optimization control as ImageReady's Optimize palette. Unless stated otherwise, the file optimization methods given in these tasks work in either program.