NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Lunar contrast
From: Geoffrey Kolbe
Date: 2016 Sep 11, 19:46 +0100
From: Geoffrey Kolbe
Date: 2016 Sep 11, 19:46 +0100
Where would be the best location for a polarizer in the sextant's light path?
I taped a polarizer directly to the objective end of the sextant telescope.
When the moon is waxing you would want to view the moon through the horizon mirror so the handle of the sextant will be underneath the sextant. When the moon is waning, you will want to view the moon through via the index mirror for the same reason. It follows that either of the mirrors is NOT the place to put the polarizing element. The rubber eyepiece of the sextant might have a little lip around it in which a small glass or plastic filter element can be placed. Otherwise, polarizing elements for cameras can be obtained for very reasonable prices in many different diameters and some means of fixing these in front of the object lens can be contrived. Once in place and adjusted, it probably need never be removed.
Geoffrey Kolbe
