Preparing Images for U-Discover!
Now that you can make visual presentations to the
outside world, how should you go about it? Here are a few tips. The key
concepts are moderation, efficiency, and
discretion.
- Moderation means optimizing your use of
images by using them where and how they are most effective. Consider the
information you want to make available, and look at the images you are
thinking of using. Are they all essential to your presentation? For
example, you do not need to use the University logo more than once per
document.
- Efficiency means getting the most information to your
audience in the shortest time. This is as true for the World Wide Web as
it is for a book or a magazine. On a computer network, this means keeping
the number of files you are using and the size of these files as small as
possible. Look at each image by itself. How are you using it in your web
document? Is it the main artwork that will go at the top of your home
page? Or, might it best be used as a small graphic to add "color" to your
text? Can the information contained in the image be quickly understood at
a small size? Reducing a graphic a little bit often saves a lot of kilobytes. Is there "dead space" in your graphic that can be cropped out
so you can zoom in on the essential part of the image? Close-ups, even
details, can carry a lot of punch and can be read at small sizes.
- Discretion here simply means respecting others. Copyright rules are
as important on the World Wide Web as they are in other media.
If you use an
image that belongs to someone else, make sure you have their permission
to use it in this particular way, and be sure to include any necessary
copyright information. If you aren't sure who owns an image, don't use
it until you are.
Technical Issues
- Make sure your images
are in a file format that is universally readable. The Graphic
Interchange Format, or Compuserve GIF, is very good for this.
Conversions can be done in graphics editing programs like Adobe Photoshop
or Graphic Converter.
- Start with the highest quality graphic you
can. Scan photos and illustrations at the highest dot resolution and the
greatest color depth available to you. 300 dpi and 24-bit color (this is
also called 32-bit color) are good starting points. Do your image editing
(color correction, sharpening, brightening) on this original file, and
only then begin to reduce the file size.
- Next, reduce your working file to 72 dpi.
Higher resolutions will not be appreciable on a computer
screen.
- Indexing is the process of reducing the number of
colors in your document. Your final file should have no more than
256 colors. Many non-photographic, illustrative images are published in
256 colors where they only need 16. This will further reduce the size of
your file. Some graphics editors offer you choices as you go through this
process. Choose anti-aliasing, adaption, and diffusion dither, where
these choices are offered.
- Finally, if you have questions, contact
the Publications Office (831-2144 or
publications@mvs.udel.edu).