Accession Number : AD0282623

Title :   ASTROMETRIC INVESTIGATION OF A BAKER-NUNN CAMERA

Corporate Author : ELECTRONIC SYSTEMS DIV L G HANSCOM FIELD MASS

Personal Author(s) : EICHHORN,HEINRICH

Report Date : 25 JUL 1962

Pagination or Media Count : 1

Abstract : The images of 1547 stars from the ''Bonner Durchmusterung'' which appear on a film taken with a Baker-Nunn camera were measured on a Mann two-screw measuring machine in 22 sittings, extending over a period of more than 100 days, during which time the film was left in the measuring machine. An attempt was made to check the creeping of the film with respect to the measuring machine, by frequently measuring four crosses which were scratched into the emulsion near the edges. Whatever creeping of the film occurs can fairly satisfactorily be represented by an affine transformation. More than four fiducial marks would have to be measured in order to check the film creeping during the measurements more accurately. By selecting the 823 AGK2 stars in the frame, and using them as reference stars, the systematic errors of the positions which depend on magnitude and color were established. The accuracy of a star position obtained from a Baker-Nunn film was obtained. (Author)

Descriptors :   *ASTRONOMICAL CAMERAS, *PHOTOGRAPHIC RECORDING SYSTEMS, *SATELLITES (ARTIFICIAL), DISTORTION, ERRORS, MAPPING, MEASUREMENT, OPTICAL IMAGES, PHOTOGRAMMETRY, PHOTOGRAPHIC ANALYSIS, PHOTOGRAPHIC EMULSIONS, POSITION FINDING, PROJECTIVE GEOMETRY, STARS

Distribution Statement : APPROVED FOR PUBLIC RELEASE