ABSTRACT
The Pleiades loose cluster is the most distinct cluster of bright stars that are visible to the naked eye. The hot stars of M45 hold a surprise; they are surrounded by a blue reflection nebula, which becomes more apparent when the exposure depth is increased and careful stretching boosts the background levels during processing. The difference in intensity between the stars and nebulosity is extreme. The image preview on a digital camera is deliberated boosted using an image stretch, called a gamma correction, to match the perception of the subject. Similarly, when a RAW file is viewed in a traditional image editor, it does the same thing and once it is converted to an editing format like JPEG, TIFF and PSD, the stretch is permanent and the image is said to be no longer linear. DeepSkyStacker is highly automated and the pre-processing steps happen behind the scenes, with a few pop-up opportunities to customize the operation.
