Inspired by Scotts H Alpha image thought I would really push the limits with exposure to bring up the faint Halpha around M42.
Details
Canon 5DH, Orion 100ED with Astro Physics focal reducer so 640mm at F6.4, Hutech LPR filter, 3X20 min at ISO 400, corrected for flats with ImagesPlus, stacked with RegiStar, digitally developed with IP, levels in PS.
900KB
http://members.optusnet.com.au/~cheekyfish/M42_H.jpg
Bert