Re: ATM Unobstructed Optics Viewing

[epabcc@epa.ericsson.se (Bratislav Curcic)]

>  Would you venture to say if you had two scopes, a refractor and reflector
> with the same high precision optic errors,  AND  the same "effective" light
> gathering aperatures (factoring in the obstruction of the Newt)...that the
> contrast is no different due to the obstruction??

No, I wouldn't. There are many reasons why a refractor is a better 
choice for dedicated planetary observer (less scatter, high entrance pupil,
no/little tube current, inherently beter baffling AND no central 
obstruction), but there is one important against : there is NO 20" APO in
existance, and even 12" ones are difficult/impossible to get. 

Bratislav