Dave, Roland, Bert and Chuck, thanks for responding. Your comments have been helpful so far. The scope is actually a 14.5" f7.65 system. I think that the corrector will be similar to the 12" system, but will have some differences based on the specific application. The focuser is one of the AP 2.7" focusers, and I'll be using one of the Lumicon refracor easy guiders. I don't have the dimensions of that device handy. Here are the specs for the scope that I have in hand:
Focal length: 2875mm
Primary: 14.5" f/2.67
Secondary: 5.5" 2.86x amplification
Mirror spacing = 25.625" = 650.9 mm
Back focus: 12" from front of the primary; 9.0" from back of scope.
Baffles: Primary - 3.5" I.D., 13.5" projection from primary; Secondary - 6.0" O.D., 2.375" projection from secondary.
As Dave Rowe pointed out, I'm sure that the AP field flatteners aren't going to deal with this all that well. I had not considered that there would be correction for coma in a refractor corrector, but any coma correction would, of course, introduce "negative" coma into the images. Also included in the optical test report is a set of Seidel Aberration Coefficients, which I am not proficient enough in optical theory to read/interpret correctly. There is mention of astigmatism, but again, I'm unable to correctly interpret the chart.
I do not yet know the amount of Back Focal Length I need, though I suspect that the 9" should be enough. It is my understanding that since the system RoC will be upwards, the basic correction will increase BFL.
Is what I'm trying to do a lost cause, or would it be worth the effort?
-- Gil