Re: [ATM] Grinding questions

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

A corrector plate is essentially doing the job of providing a correction to
the lightpath so that when the light hits the primary it acts as if the
surface was a paraboloid without the corrector plate.  The corrector plate
makes a difference as the light is modified at the FL of the primary so that
the spherical surface will properly reflect the light to the focal plane as
if the surface was a parabolic surface unique to each direction of the
light.
As such, the corrector plate is made for a particular focal length of the
primary and, while small differences won't be significiant, large changes
will as the error bands for the Foucault test will be in effect.
Bob May
bobmay@nethere.com
http://nav.to/bobmay
http://bobmay.astronomy.net

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