Do you know which type of electronic file to use when? Raster and Vector are the two main file formats used in graphic production, but their strengths are very different.

Raster files (or bit-mapped files) are the best choice for photos and images that require subtle gradations of colors. They are not good for enlarging or rotating images. They are resolution dependant, meaning that they can be decreased in size without apparent loss in quality, but they cannot be enlarged without noticeable rastering (jagged edges). Depending on the desired resolution, Raster files can be very large in size. PhotoShop® is the most common program used to create Raster files. It is imperative to know the largest size of a Raster file that will need to be used before the file is scanned or created. All photographic images should be created in Raster format.

Vector files can be reduced, enlarged, rotated, reshaped or refilled with no loss of quality. Vector files are created by programs such as Illustrator®, Freehand®, Canvas®, Coral Draw® and Photoshop® 6 (type treatment and line art only for the latter). Vector files usually have relatively small file sizes. They cannot incorporate photographic images, they occasionally have problems with smooth gradations and they can only be saved out in an EPS (Encapsulated PostScript) format. All logos and non-photographic elements should be created in Vector format.