makeepss, makepdfs, and makewebs process by default all graphics in your document. This may be annoying, because it usually consumes a long time and you only want to re-create one graphics. Therefore they accept an optional argument which is the name of a graphics. If it's given, they process only this graphics, as in
This (re-)creates only the web version of the graphics that is included with
in the tbook document. Similarly you can give eqn-<number> to makeeqns:
You can find out the number of the equation that you want to have re-created by using your browser to see which bitmap filename the formula has.