NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Sextant Filters / Nearsighted CelNav?
From: Fred Hebard
Date: 2006 Apr 23, 18:48 -0400
From: Fred Hebard
Date: 2006 Apr 23, 18:48 -0400
Welcome Greg, I have a Husun scope and a Cassens + Plath. In both of those, all the filters are the same color, so I'm not sure what the purpose is for the Davis filters. There have been some comments on the list lately about the uses of those filters. However, as a first guess, one would put down the needed number of filters to darken the sun or moon. Fred Hebard On Apr 23, 2006, at 5:53 PM, Greg R. wrote: > 1) What (if any) is the specific usage for the different-colored > filters (i.e. blue, amber-orange, grey, etc.) [on a Davis Mk 25]? I > know that for a really bright sun you'll normally want to have all > of them down (4 in my case), but is there ever any case where you'd > want to use them either singly or in combinations? I would guess > that the amber-orange one could be used on the horizon to sharpen > it up on a hazy day, and the grey one obviously knocks down the > brightness a bit, but where would you use the blue one(s) (mine has > two of them) or maybe other combinations?