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Web Images

( back to do's and don'ts )

Effective use of images on the web is a complex subject that requires a specialist.

Image Formats
Computer files are written (or "coded") in what are called "formats" or "coding methods."  The two types of image formats that work on the web are the "jpeg" format and the "gif" format.  Both are methods for compression, which means that the images are reduced in file size so that they may be displayed on the monitor screen within a reasonable amount of time.  Images designed for print are simply too large for the Internet.  Reducing the file size, while still retaining the quality of the image, is the art of processing images for the web, and there is no substitute for expert help in this area.

• Gif images

  Gif images are produced by reducing the number of colors used in the image.  This makes for a smaller file.  Gifs are best for smaller images, say 100 X 100 pixels or less, and also for images which require fewer colors to display properly, such as  logos.

• Jpeg images

  Jpeg images are compressed in size by having a computer program search for strings of adjacent pixels in the image that are the same, or nearly the same, color.  There is a wide range of ratios available in the Jpeg format, and the optimum balance between file size and image quality is best done by a professional.  Jpeg files are best for complex images such as photographs.