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Old November 29th 05, 06:23 AM posted to sci.astro.amateur
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Default Making a homemade focal reducer

I want to make my own focal reducer for my 11" SCT. Can anyone tell me
how to figure
the actual focal reduction based on the f.l. of the achromat lens?
There are several
48mm achromats available online with focal lengths from 208mm to 360mm
(I think).

Any help is appreciated. Thanks.