The Astro Record program is aimed at making position measurements of celestial objects, especially meteors, and performing the associate astrometric calculations. For this purpose screen coordinates of the object and of a number of reference stars can be measured, equatorial coordinates of the reference stars can be looked up, and the results of the astrometric calculations can be analyzed regarding wrong star identifications and plate defects.
The results are stored as an output file that can be used for either the Turner or Redsky astrometric computer programs in use within the Dutch Meteor Society. In addition, the equatorial coordinates (equinox J2000.0) of the meteor's begin and end point are stored in a log file that can easily be converted to the PosDat format used by the International Meteor Organization.
The program can handle images in the Windows Device Independent Bitmap Format (*.BMP), Kodak Photo CD format (*.PCD) or Video for Windows format (*.AVI). For obtaining the equatorial coordinates the program uses the Sky Catalogue 2000.0, Vol. 1, second edition,1991 (c), sold by The Sky Publishing Corporation. The entering of equatorial coordinates is eased by the possibility of specifying a constellation name and Flamsteed number. From the fourth star on the program predicts the most probable star from a list of possible stars, based upon the previous measurements.
For the astrometric calculations the equatorial coordinates are converted into so-called direction cosines and expressed as a polynomial function of the screen coordinates x and y (Turner's method). The user can choose between a first, second or third order fit. A third order fit can compensate for the most common image distortions due to camera and projection lenses, Photo CD production, optical scanning, image intensifiers, etc.