  We present a World-Wide-Web-accessible database of astronomical images which
suffer from a variety of observational problems, ranging from common
occurences, such as dust grains on filters and/or the dewar window, to more
exotic phenomena, such as loss of primary mirror support due to the deflation
of the support airbags. Apart from its educational usefulness, the purpose of
this database is to assist astronomers in diagnosing and treating errant images
at the telescope, thus saving valuable telescope time. Every observational
mishap contained in this on-line catalog is presented in the form of a GIF
image, a brief explanation of the problem, and, when possible, a suggestion for
improving the image quality.
