A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Tony Oz
Date: 2017 May 24, 23:42 -0700
The scope's focus is definately not on the mirror, it is on the object.
What I was surprised to discover is that my monocular needs different focus for a light-house some ten km away and for a star. If it were a photocamera's lens - to my experience everything at 25 meters or further - is at the "infinity" (according to the lens' marks).