Study of sky condition at Raipur and calibration of the photometer-telescope system

Abstract

To investigate local sky condition for valuable astronomical observation, we obtained values of atmospheric extinction coefficients in BVR filters for over 150 nights during the period of 1994 to 1997. Our observation over nearly three years indicates that although the sky condition at the observing site is not steady, the observing facility can be fully exploited for differential photometric studies on bright variable stars. Several times during each observing season on clear photometric nights we also carried out observation for calibration and checked reliability of our system calibration.