by Richard Crisp
This is an image of the Crab Nebula taken using five different methods. Starting at upper left: LRGB, Emission line (Sulfur, Hydrogen, Oxygen), Stokes Polarigram, Polarigram and (center) composite Stokes Polarigram and emission line.
Shot using home built 18" f/12.6 classical cassegrain at f/7.3 (F=3366mm), FLI CM10XME camera, Custom Scientific emission line filters, Optec RGB filters and Edmund Scientific Linear polarizing filters
Total exposure time was 5 hours