Hi all --
I bought a 16" spherical mirror which has a radius of curvature of about 35". It has a 4.25" center hole. I bought it as a tinker project and am wondering what I should expect if I have the mirror ground to a parabola with the same 35" focal length. A 4" secondary would cover the mirror and place focus just about right. I'm guessing that there'd be a lot of edge coma, but how good could I expect image quality to be otherwise?
Or would a Cassegrain approach be more likely to produce decent images? And where would I look for a Cass. secondary?
Funds aren't limitless but I wouldn't mind spending some money and time if there was reasonable prospect for success.
Thoughts/ideas? Thanks for any help.
Bob Polcyn
I bought a 16" spherical mirror which has a radius of curvature of about 35". It has a 4.25" center hole. I bought it as a tinker project and am wondering what I should expect if I have the mirror ground to a parabola with the same 35" focal length. A 4" secondary would cover the mirror and place focus just about right. I'm guessing that there'd be a lot of edge coma, but how good could I expect image quality to be otherwise?
Or would a Cassegrain approach be more likely to produce decent images? And where would I look for a Cass. secondary?
Funds aren't limitless but I wouldn't mind spending some money and time if there was reasonable prospect for success.
Thoughts/ideas? Thanks for any help.
Bob Polcyn
