17014

We monitor the WFC3 UVIS shutter performance. The exposures need to be identical to previous cycles. Images with exposure times ranging from 0.5 to 17 seconds will be used to compare the photometric behavior of each shutter blade comma for short vs long exposures and check for shutter shading effects. The first exposure of 0.5sec cannot be used since the lamp would be still heating during this exposure comma so we will take a set of three 0.5sec exposures. Internal flats in each of the 4 amps will be used to monitor the repeatability and shutter shading effects.