A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2016 Nov 1, 11:54 -0700
Bob & Noell,
On the Davis MK3 do not use the sight tube filters for direct Sun viewing such as limb to limb Sun index error determination. It is best to use the horizon for this or add Thousand Oaks solar film to the sight tube which will allow for direct viewing of the Sun (see image of sight tube). As for filtering index mirror Sun observations both filters need to be in place for a bright Sun. If it is still too bright then add one of the sight tube filters. Better yet is to attach solar film to the green index mirror filter for best eye protection from a bright Sun (see image).