Digital image centering. IA series of parallax plates have been measured on a PDS microdensitometer to assess the possibility of using the PDS for precision relative astrometry and to investigate centering algorithms that might be used to analyze digital images obtained with the Large Space Telescope. The basic repeatability of the PDS is found to be plus or minus 0.6 micron, with the potential for reaching plus or minus 0.2 micron. A very efficient centering algorithm has been developed which fits the marginal density distributions of the image with a Gaussian profile and a sloping background. The accuracy is comparable with the best results obtained with a photoelectric image bisector.
Document ID
19760039417
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Van Altena, W. F. (Yale Univ. Observatory New Haven, CT, United States)
Auer, L. H. (Yale University Observatory, New Haven, Conn., United States)