Abstract:
The achromatic aberrations, which in general affect image quality in telescopes, have been studied in context of the 1.2 m Gurusikhar Infrared Telescope. The analysis gives the magnitudes of aberrations for different fields of view at the Cassegrain and prime focus thereby indicating the optimal field diameter that may be used for observations. The range of acceptable back – focal distances have also been worked out, thereby setting constraints on the location of the focal plane in back – end instruments to be used on the GRIT. This study should be especially useful while designing instruments for the 1.2 m telescope, in planning observations or in subsequent data analysis
