NavList:

Bill asked:

> "More to the point, is there some way to mathematically null out the  eyeball
> problem..."

Frank responded:
> I don't have a mathematical solution per se, but  there is a simple practical
> solution. I recommend the use of correcting glass  plates in front of each
> eye. These plates can be installed in a frame which  might rest on the bridge
> of
> the nose, perhaps with supporting frames wrapped  around the head or at least
> to he wearer's ears. You could grind your own glass  plates, or possibly a
> local optical shop could produce them for you. The  supporting frame might be
> made of metal wire or perhaps an attractive plastic.  :->

Ah! A composite prosthetic device fabricated from a combination of metal,
plastic and/or glass designed to be supported by the nose and ears!

Will use of a prosthetic device allow me the use of handicap parking spots,
or better yet handicap slips?  As a sidebar, I have never seen a slip with
blue dolphin poles, blue finger piers, and a wheelchair painted on the
water.  Wonder why? (No offense meant to handicapped/mobility-challenged
sailors).

> You do have eyeglasses, don't you? Perhaps a Bauer-esque monocle?

I see the limit on the 24-to-48-hour rule has passed ;-) Bauer spent over
three pages, photo illustration included, under the subhead of, "EYEGLASSES,
THE NAVIGATOR'S CURSE." My Cliff's Notes from two-plus pages of text is that
the Rube Goldberg monocle is used to read the instrument.  (If memory
serves, he speaks of taking sights with his right eye, yet the "monocle" is
over his left eye in the photo.) Upshot, if you can take the sight "bare
eyed" do it. 

Other practical considerations:  My eyeglasses reduce the problems but do
not eliminate them, and contact lenses my not fully deal with astigmatisms
either.  A personal factor is still called for.

Of greater importance, not all scopes have enough eye relief to allow the
use of eyeglasses.  Due to my facial structure and prominent proboscis
(noble Roman nose) I give away nominally 16mm between the eye and eyeglass
lens. Nominally 8 mm from my 3.5X scope's ocular lens to the hard-rimmed
eyepiece extension.  Do the math.

http://www.binocularsmart.com/how-to-choose-binoculars.shtml
http://www.yesmag.bc.ca/Questions/binoculars.html

"Finally, if the phrase ŒEye Relief¹ is mentioned, then it refers to the way
that the eyepiece is set up with respect to the other optics in the device.
Most glasses (binoculars) will come with eye relief between 9mm and 13mm,
and is the distance from your eye to the lens before your field of view
becomes limited.

If you wear eyeglasses, then eye relief above 14mm becomes desirable, since
you will already have a certain amount of distance between your eye and your
eyeglass lens, which you can not change. Given this, if your chosen optical
device has a small eye relief, then you will have a very restricted field of
view, and miss out on most of the picture!"

And

"Look for binoculars with longer eye relief. Not only will you enjoy more
comfortable viewing when the eye relief approaches 15mm or more, but this
distance opens up a fuller field of view to you. You'll find binoculars with
eye relief measuring from 5mm to 23mm ‹ the distance from the ocular lens to
where images are projected at the focal point."

Imagine lining things up on a light/medium displacement small craft with a
star scope that has significantly less field of view than a 6X sun scope.
Not gonna happen. As the Guinness Beer commercial states, "Brilliant." <G>

Horse-Face Willie AKA Wooly Bill








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