Re: [ATM] 16" RCC primary

[Jeff Rowe <jroweapp@swbell.net>]

Vlad;

These both sound very interesting. In the book Telescope Optics 
Evaluation and Design    by Rutten and van Venrooij, Willman-Bell 1989, 
they give an example of a Loveday design on pg. 135. It is a 200mm f24 
and it looks really nice, as far as spot diagrams.  How do your 2 
examples scale up to a ~400mm primary?  What would be their EFL and the 
size of the secondary and tertiary mirrors? I'm not interested in exact 
figures, just an approximate idea.
Thanks
Jeff Rowe  Texas

>
>If the instrument is intended for imaging, you could consider Loveday's
>arrengements (primary reflects light from the secondary back, focusing
>through an opening at the secondary), either with paraboloidal or 
>hyperbolidal
>primary. They would require much less aspherising. With an f/4 paraboloidal 
>primary,
>an effective f/8.7 system would regure -1.7 secondary conic, with nearly 
>half
>the coma of the Classicial Cassegrain counterpart.
>
>With hyperbolidal primary (-1.2), the secondary is -2.5 and the system is 
>coma free,
>with ~2.5 times less astigmatism than comparable RC, and about about twice
>milder field curvature. While there shouldn't be much difference in 
>performance
>for the intended purpose within the given field, the RC mirrors are harder 
>to make.
>
>Vlad 
>
>_______________________________________________
>ATM mailing list http://www.atmlist.net/
>


_______________________________________________
ATM mailing list http://www.atmlist.net/