Digital printing file requirements?

Postscript format is preferred for large format work; .ai, .eps or .pdf. Please convert all fonts in file to outline form (Command-shift-O in Illustrator) or provide the Type 1 or True type package along with your file.
Bitmap format is also supported; .ps, .tif, .jpg, .gif. We recommend an RGB format with an ICC profile, preferably “Adobe RGB (1998)”. You may also send CMYK files, please use the “US Web Coated (SWOP) v2” ICC profile.

Bitmap resolution must be adequate for the level of enlargement. Guidelines for resolution are based on viewing distance:

• Viewing distance/ Resolution at FULL PRINTED SIZE / File size (RGB, multiply file size by 1.33 if using CMYK format) *Note that this is the uncompressed size, open your file in Photoshop and refer to the file size shown in the “Image Size” window.
• 1′ / 300 ppi / 37.0 Mb/sq. ft. RGB
• 3′ / 200 ppi / 16.5
• 4′ / 150 ppi / 9.3
• 13′ / 100 ppi / 4.1
• 18′ / 50 ppi / 1.0
• 30′ / 20 ppi / .2

For example, a typical 24″x36″ trade show poster viewed at 3′ should be 200 ppi at full size, or a full uncompressed 99 megabyte RGB file. (6 sq ft * 16.5 = 99 Mb) The same poster viewed from 4′ need only be 56 Mbs to achieve the same visual sharpness.
This applies only to the final size of the bitmap area in your design, not the entire size of the print (Postscript-only print
areas are independent of resolution concerns).