Source detection is an important and delicate process as the background and all the sources (especially the bright ones) in the field of view will have an impact on it. Because of this intrinsic complexity of the instrument, there are different options as far as source search and background correction are concerned. The choice of the best method to use for a given case may require a bit of iteration on your side.
In the next two paragraphs we describe the parameters involved in the source search, along with some practical advices. The single Science Window case is treated in Section 8.2.1, while the mosaic image case in Section 8.2.2. Comments on the background subtraction issue are given in Section 8.2.3 while a set of miscellanea on imaging parameters is given in Section 8.2.4.