"venera 9" measured clouds that were thick with bases at altitude. it also measured atmospheric chemicals including hydrochloric acid, hydrofluoric acid, bromine and iodine. other measurements included surface pressure of about , temperature of , and surface light levels comparable to those at earth mid-latitudes on a cloudy summer day. "venera 9" was the first probe to send back black and white television pictures from the venusian surface showing no shadows, no apparent dust in the air, and a variety of rocks which were not eroded. planned 360-degree panoramic pictures could not be taken because one of two camera lens covers failed to come off, limiting pictures to 180 degrees. this failure recurred with "venera 10".