One of the major factors driving people away from your web site are long loading times. In most cases, this is simply due to too many graphics that are too big in size.

That said, let's assume you really need a graphic, for some good reason. This does not mean, it must be a BIG graphic. It should simply be enough to give your visitors any sort of imagination. Ask yourself: "Will a visitor really ever want to track it down to the finest detail? Or will a cursory overview be sufficient?"

If you come to the conclusion that a smaller graphic would do as well, you have several ways to achieve that. (What, by the way, will not only save load time. It will also give your web site a flavor of "professional design". Your web site will create an impression like "Oh, they were really worried about showing exactly what is in place here!")

So you can simply REDIMENSION the total picture, to make it smaller.

Sometimes redimensioning will cause irritating "Moirés" (as photographers call the unpleasant patterns appearing when fine details are too close together). Then it might be worthwhile to CROP the total picture, or to present only a CUT-OUT of it.

Sometimes, however, you really need the total picture. And the visitor should still be able to see some details. Then you should ask yourself: "Is near-perfect coloring really needed?" If not, most of the modern image file editors offer a number of other ways to bring down the size of an image file. You could use, for example, 4bit-bitmaps instead of 8 bit. You could reduce the color depth from 24 bit down to 16 bit. You could increase the compression of jpg-files. (Don't have a modern image file editor? You can download a shareware 'Lview Pro' from  http://www.lview.com/  ).