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allan gould
21-11-2006, 04:05 PM
While trying to photograph the horsehead nebula (which according to a star map and Maxwell Smart I missed by "that much" - just in upper right quadrant out of frame), I at least managed to photograph the Flame Nebula. But with Alnitak in the frame you can see the internal reflections of having too many uncoated surfaces in the light train. The main optics are from a very old celestron 8" sct with absolutely no coatings what-so-ever. Also my colimation was slightly off as can be see in the faint doughnut overlying the Flame Nebula. Oh well, next time I'll get the horse.

tornado33
21-11-2006, 04:47 PM
Youre in fact lucky, my uncoated Meade 6 inch F3.6 schmidt newtonian corrector plate give awful reflections, and as the secondary is off axis mounted, the reflections look odd and out of shape.

If youre really keen you could give the corrector plate to Issac of
http://www.opticalcomponents.com.au/
Thats him in front of a coating plant.
He could do a front and rear surface antireflection coating for you.
Scott