###ACS FOIBLES ###

     * How bad is the fringing at wavelengths longer than 7500 Angstrom ?
     Like most CCDs, the ACS CCDs show fringing in the red for monochromatic
     light at wavelengths longer than 7000 Angstrom. The amplitude of the
     fringes is a strong function of wavelength and source monochromicity.
     At the time of writing the ACS HAndbook (June 2000), we do not have good
     figures for the amplitude of the fringing; a preliminary investigation
     shows that fringing in ACS is less severe than STIS (see ISR Bohlin,
     Hartig and Tsvetanov, in preparation).
     Work is in progress to reduce residuals of fringing to <= 1%.