Posts Made By: James Koerth

August 3, 2022 09:06 AM Forum: Refractors

Refractor objective lens

Posted By James Koerth

Could I put a 127mm 1200mm focal lens achromatic doublet objective lens in a refractor that currently uses a 127mm 1180mm F9.3 doublet objective lens.  How would the 20mm affect draw tube focus if it could be done?  Thanks for your advice.

Jim Koerth
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