NavList:

   

Reply

On 9/20/2014 1:56 PM, Frank Reed wrote:
> if you avoid lights, you'll be able to see the horizon earlier than
> normal. In evening twilight, this is harder to arrange since it takes
> about fifteen minutes to become properly dark-adapted. That fifteen
> minute period happens to be roughly the pace of the transition from
> light to dark in twilight, so in evening twilight, by the time you're
> dark-adapted it's probably too late...

I carry an eye patch in my sextant case to dark adapt my shooting eye if
necessary. The downside is monocular vision, so caution must be
exercised if moving about the craft.

Dark adaption is not always beneficial. Many years ago Frank pointed out
an article which explained the larger the pupil aperture, the more a
point source point source became a spiked object. I would suggest being
guided by the magnitude and location of the preselected bodies. In the
case of Polaris, a definite yes. Venus, not so much.

On September 19th (International Talk Like a Pirate Day) it should
always be worn.

   

Reply