Dear All,
I played around with OSLO to found out what is the optimal
positioning of the Schmidt plate with the classic C14 design (ie.
not relevant to the Edge-HD).
It turned out that if the Schmidt plate is set 400 mm ahead of
its original position, the radius of the field limited by
diffraction is enlarged by 4 (9 arcmin instead of 2.2 arcmin).
This is not as large as the C14 Edge-HD (12.4 arcmin) but not far
away.
Of course, the optical tube becomes much longer (there is no free
meal ...).
The other optical characteristics do not look to be affected
(Strelh ratio on the optical axis, variation of focus with
wavelength).
More information here :
Best regards
Christian Viladrich