[QUOTE=Saturnine;1617077]
Quote:
Originally Posted by Stefan Buda
The DK is definitely not an astrograph and it is as good as it gets for visual planetary.
I am presuming that it would still be good for planetary and lunar imaging though, which is what I'd focusing on with it, if I do manage to obtain one.
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Of course it is. You don't need an astrograph for planetary imaging, but you do need one for deep sky.
For planetary imaging only two aberrations need to be corrected, and those are the spherical and the chromatic aberrations. Coma, field curvature and astigmatism don't come into play with the small field of view needed.
Astrographs actually compromise a little bit on the spherical aberration but not enough to matter at, say, one arc second resolution, but that amount of compromise becomes detrimental at, say, 0.4 arc second planetary contrast.