Re: ATM Where's your 100% Light cone?

[andydtg@alpha1.phoenix.net]

   Jon Bertrand wrote:
>     I'm curious about the 100% illumination size of everyone's Newtonian.  
>     What's a good size for the 100% (and 75%)?
    
I design mine to have a 1.1 to 1.3" unvignetted field size. This
fills the center of a 35mm frame and fully illuminates long f.l.
eyepieces, for a deep sky scope. For planetary/lunar obs, CCD, 0.5"
or even less is sufficient.

Keep in mind that in a few years, CCD cameras will have affordable
chips 1" square or larger!


Andy Saulietis / DTG Alt-Az-Fp Drive Systems
12617 Harriet Ln
Santa Fe, TX 77510 USA
409-925-8854 Voice/Fax