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The Crab Nebula is difficult from New South Wales - low to the North in the heat of summer, with correspondingly appalling seeing (10 pixels = 5.5 sec arc FWHM), but it is special enough for us to have a go.
Perhaps in retrospect narrowband (H-alpha 6 hrs, OIII 3hrs) was not the best approach, because the blue glow of the Crab is largely synchrotron radiation and not best suited to an OIII filter.
Note the faint extension toward the left hand side of the image.
Field of view cropped to 18 min arc. Aspen CG16M on 20" PlaneWave.
H-alpha to R+G, OIII to blue, then rotate palette -15 degrees.
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