Re: [ATM] Another flat-field anastigmatic aplant

["vladimir" <svla@isp.com>]

Richard F.L.R. Snashall wrote:

> Before it gets to one-fifth of that, the unvignetted diameter at
> the hole in the primary is larger than the secondary size.  Just
> curious: what would you suggest as the final size for that hole?

Secondary size is small to begin with (less than 17% the primary 
linear size in this particular system). Even that small, it is probably 
large enough to accomplish its baffling role, due to close proximity 
and small diameter of the front baffle opening. As such, it is not a 
factor in the effective c.obstruction of the system. The primary central 
opening would be determined as a compromise between the max field 
diameter obtainable with the largest acceptable size of c.obstruction. 
If ~1-degree fully illuminated field (and somewhat wider useable field) 
is large enough, central opening somewhat larger than 0.4D 
should do.

Vlad
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