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Old 20-12-2012, 05:21 PM
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Satchmo
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Join Date: Dec 2005
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Quote:
Originally Posted by wulfgar View Post
So if all that is true.

Why does a spherical mirror work for an F12 and is something of a disaster in an F4?
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Err...now I see where you are coming from ...who makes a spherical mirror these days ?

A 6" F12 has acceptable level of spherical aberration. (probably 1/8 wave wavefront). However the manufacturing tolerances on the surface are no greater than an F4 ....
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