Next: To Restore or
Some Problems of Practical Image Restoration
Ivan R. King
Astronomy Department, University of California, Berkeley, CA 94720
Abstract:
This discussion begins by noting that stellar photometry is often done
quite effectively on unrestored images. Even when restoration is
necessary, one must be wary of sophisticated methods, many of
which distort photometric values. Fourier methods are photometrically
reliable, and Wiener filtering leads to reasonably good restorations. The
statistics of pixels in a restoration presents new problems, which have
been only partly solved. A completely unsolved problem is presented:
estimating the arithmetic difference between two images that have different
PSFs and different 
. The discussion concludes with a plea for
methods that are available and transparent to the ordinary user of HST.
This is likely to be the least technical and most nave of all the papers
presented at this meeting. I come before you not as an expert but as a
user, and not as a contributor but as a consumer. I could suggest that I
am on the invited program only because I can't convince Bob Hanisch that I
don't know anything about image restoration, but that would not be totally
fair. I think that Bob really did want you to hear from some people who
represent the user community of image restoration. I do have a certain
amount of experience with it, and I have some scars to show for it.