GRAVITATIONAL LENS SYSTEM Q2237+0305 IN 2001-2008: OBSERVATIONS ON MT. MAIDANAK

The multicolor photometry of images of gravitational lens system Q2237+0305 taken in 2001 to 2008 with the AZT-22 1.5 m telescope (Mt. Maidanak, Uzbekistan) is presented, the photometry procedure applied briefly described. Comparison of our photometry results with the OGLE project data has allowed the reduction relation between these sequences of data. The photometry errors have been estimated, these of the OGLE project are shown to be slightly less than those in our measurements. Quantitative assessments are obtained for the relations between the Q2237+0305 system brightness variations produced separately by microlensing events and inherent quasar variability.