Re: [ATM] Slit and source arrangment

["Bob May" <rmay@nethere.com>]

As I see it, the difference in location of the axis of the source
and the return beam will cause an apparent measure of an
eliptical view.  This is obvious as the two loci of the foci are
in different places i9n the layout.  If you place the two axis
beside each other, you will have some residual amount of error as
you won't be measuring the spherical surface but rather a
eliptical surface.  If you plac the two axis one above the other
(assuming that the KE is vertical, of course) then the eliptical
error will be hidden in the fact that you're not measuring the
mirror in that direction.
Depending upon the size of the mask holes in the vertical
dimension, you may never see any of the error generated by the
single KE occulding both the light source and the viewing return
beam, especially if the light source is close to the return beam.
Bob May

rmay at nethere.com
http: slash /nav.to slash bobmay
http: slash /bobmay dot astronomy.net


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