ATM All Sky Instrument

["John D. Gwinner" <gwinner@northnet.org>]

Folks:

  On the TASS (The Amateur Sky Survey) list, they've been talking about an
all sky instrument.  In this case, they are using 2k x 2k CCD's and widely
available cheap camera lenses, but recently there's been some discussion of
using a Schmidt camera or other instrument.  They want LOW F ratio; say F2
or F1.4.

  What would be the best optical design for that?  Wouldn't a Newtonian
have a lot of coma at this F ratio?  Schmidt cameras would have none, but
could you accommodate the curved focal plane with the CCD?

  A few people have suggested removing the secondary on a commercial
(Meade) schmidt camera and converting to prime focus CCD imaging.  

  Thoughts?

  Costs?

                == John ==