Detecting Stars in Crowded Stellar Fields

A comparison is made between some conventional and new methods for detecting stars in crowded stellar images. The new methods are (1) Lucy-Richardson deconvolution of the image before detection, and (2) fitting the Point Spread Function to each pixel in the image. These methods are applied to both a synthetic image and a real one. The deconvolution method looks very promising, and gives better results than the conventional ones, provided a large number of iterations are applied. 1 Introduction To be able to measure the position and intensity of stars, these have to be identified as such first. In the case of few stars in the image this is not a problem. As soon as stars start overlapping, problems arise that may cause stars to remain undetected. Undetected stars will affect both the measured position and intensity of a detected star. Therefore, if high accuracy is needed, care must be taken to identify as many stars as possible. One of the largest problems with detecting stars is that..