8" f2 CCD Camera

I just received an 8" f2 mirror that was for a Schmidt Camera. I would like to install a small (tubular) CCD camera and a secondary to make a camera. I believe that the primary mirror is spherical. What curve would I need on the secondary?

You could always just make a "Lenless Schmidt" camera, like this one: http://home.freeuk.com/m.gavin/schmidt_lens.htm

A two-mirror system with spherical primary would suffer from exorbitant coma. Required secondary conic to correct for both, coma and spherical aberration would be too high
to even consider making it. The next simplest solution to a "lensless Schmidt" (which in this case would require 80mm effective aperture for 0.025mm s.a. blur) would be Schmidt plate with neutral zone at the center - in effect, a very mild plano-concave lens (it would be onlu ~0.1mm deep at the center in this case). It would have four times the (sphero)chromatism of an optimized Schmidt corrector, but it would still be not more than 0.03mm at 400nm violet.