HI, i am new in astronomy; still learning things from various forums. I have a question for the experts. What are the differences between Parabolic and Hyperbolic primary mirror for a Newtonian astrograph? Provided they all use corrector lens? For example ASA have Astrograph for Parabolic and Hyperbolic mirror but both use corrector lenses.
http://www.astrosysteme.at/eng/astro..._h-series.html
As far as i know Takahashi Epsilon also use Hyperbolic mirror. And it seems Hyperbolic astrograph is more expensive than Parabolic astrograph. If you need to use corrector than why use Hyperbolic? There must be some reasons which I don't know. Can anybody give me detailed explanation?