From: jim_chung@sunshine.net

Date: October 14, 2015 6:17:50 AM MDT

To: <Astro_IIDC@yahoogroups.com>

Subject: Re: [Astro_IIDC] First ever AstroIIDC screen capture with a Chiefspiegler

Reply-To: jim_chung@sunshine.net

Hi Milton,

The beauty of the Ed Jones Chiefspiegler design is that you can indeed buy the optical components needed, within reason.  You are probably limited to about a 10" f/8-f/10 scope, slower & smaller diameter the better because the required planoconvex and planoconcave lenses generally top out at 50 mm diameter from commercial sources.

I have a 10" f/8 primary, a 3.5" diameter circular flat, and 50mm planoconvex/planoconcave lenses 600mm focal length.

If you want to build a bigger Chief, larger planoconvex lenses can be found (Ross Optical) but the planoconcave are impossible to source.  Have Ed Jones make one for you and it will also be optimized for perfect color correction.

If you adjust everything right you will get a perfect star test with no coma or astigmatism on axis (peripheral coma from the primary mirror will still be present).

regards,

Jim