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 S/N. The discussion concludes with a plea for methods that are available and transparent to the ordinary user of HST.
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