Re: ATM Off axis parabola

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

>> 16 inch off axis parabola

Unless you REALLY want a challenge, I simply can't see why ? If you
make it reasonably long (say, an off cut from a f/5 parabola, which
makes your 16" about f/10.5) - imagine how big such a scope will be !
If you make it manageably short (say, an off cut from a f/2.5 parabola,
which makes your scope something like f/5.5) you run into deep, DEEP
trouble of making a highly (I'd say enormously!) aspherical surface,
AND having to buy some of the best available eyepieces that can stand
~f/2.5 cone (even those will be streched to the limit!). A well made
16" f/5.5 (you have better than a fair chance to make that one _really_
well) even with a substantial obstruction will simply blow away poorly
made off axis one (and I think there would be VERY few people around
able to make such a beast to really top standard).

Bratislav