ATM Re: [Raytrace] Dall Null for 22" f4.5

["Bob May" <bobmay@nethere.com>]

You're bringing the light gathered off to the side of the primary rather
than through the middle????
If so, welcome to the wonderful world of the Shiefspieglers!  The basic
design of them is related to the Cass. designs where only an off-axis part
of the Cass is used and the surfaces are only approximated as to the shape -
which is why they don't perform as well as could be expected.
Bob May
http://nav.to/bobmay
bobmay@nethere.com
NEW! http://bobmay.astronomy.net