HDF Image Stacking:

In version 1 of the HDF processed data, CRREJ itself was used for combining the frames a stack with the same dither position. Weights were proportional to the exposure time, which is nearly optimal for the F814W and F606W, but not for the F450W and F303W images, which have a significant read-noise contribution. A different weighting scheme is being adopted for version 2.

Copyright © 1997 The Association of Universities for Research in Astronomy, Inc. All Rights Reserved.

Harry Ferguson ferguson@stsci.edu 1/14/96