The HDF observations were carefully scheduled to minimize the effect
of scattered light. Nevertheless,
Scattered light from the bright earth produces a visible X pattern
in about 25% of the HDF data frames. The
attached figure shows the distribution of mean sky backgrounds
actually obtained. The filled-in portion of the histograms indicates
data where the scatttered light patern is visible to the
eye.
In most cases the higher background
associated with the scattered light has only a very small effect on
the resultant S/N for faint objects. However, the X pattern is
not terribly pleasing to the eye, and may cause problems for some object
detection algorithms.
A major difference between version 1 and version 2 of the data reduction
was the treatment of scattered light. Details can be found below:
Copyright © 1997 The Association of Universities for
Research in Astronomy, Inc. All Rights Reserved.
Harry Ferguson ferguson@stsci.edu
3/1/96
