Re: [ATM] Is There a Difference

["James Lerch" <jlerch1@tampabay.rr.com>]

----- Original Message -----
From: "Richard Schwartz" <richas@earthlink.net>


> In optics we have the Ray-Lee criterion:   if the optical path difference is
> less that 1/4 wave, the optical system is indistinguishable from perfect.

Isn't this only true for On-Axis image?

My most recent post showed a 1/4 P-V wavefront 6" F/8 (@550nm) was only 
diffraction limited for a measly 1/20 degree field of view.  Where as a 1/10 P-V 
wavefront 6" F/8 (@550nm) was diffraction limited to nearly 1/2 degree field of 
view.

Did I make an error somewhere?

Take Care,
James Lerch
http://lerch.no-ip.com/atm (My telescope construction,testing, and coating site)
http://lerch.no-ip.com/ChangFa_Gen (My 15KW generator project)

"Anything that can happen, will happen" -Stephen Pollock from:
"Particle Physics for Non-Physicists: A Tour of the Microcosmos"

" Press on: nothing in the world can take the place of perseverance.
Talent will not; nothing is more common than unsuccessful men with talent.
Genius will not; unrewarded genius is almost a proverb.
Education will not; the world is full of educated derelicts.
Persistence and determination alone are omnipotent. "
                                                           Calvin Coolidge

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