A COMPARISON OF GALAXY IMAGES ON NEW AND OLD POSS PRINTS

Both the major axes and axial ratios of galaxy images measured on new POSS prints differ significantly from measures on older POSS prints. Diameters on new prints are systematically smaller (by ~ 14%) than those on old prints and images appear significantly rounder on new prints. This suggests that galaxy images on new prints are of inferior quality. For a sample of 37 E and cD galaxy images, we give relations between major axes and axial ratio as measured on both print sets.