WFPC2 Technical Instrument Report 00-01:
SMOV3a Flat Field Stability Check
-Koekemoer, Biretta, and Wiggs
We compare WFPC2 Earthflats taken before and after the 1999 Servicing Mission 3A. Most of the field-of-view shows no change (<0.3%) in flat field calibration. The largest changes occur only near the CCD corners, particularly near the apex, and reach ~1.5%; these are likely attributable to long-term changes in the camera geometry, rather than SM3A.