Here is my image of M45 – initially I thought the surrounding irregular background was light pollution but then I saw the other attached file as NASA picture of the day and realised it was real nebulosity!
QHY10, Sky Watcher Equinox Pro 80mm, Sky Watcher HEQ Pro mount, Sky Watcher Field Flattener/Reducer for ED80, no filter used.
68 x 60 second sub-frames, TEC @ -10C.
Stacked in Deep Sky Stacker with flats and flat darks and dark frames taken on another night.
Processed mainly in GIMP – although I used trial version of PixInsight Dynamic Background Extraction at one point in processing as well.