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Ok. I'll wade into this one.

To address Ted's note, I have my doubts if attempting a noon sight
without shades will result in a detached retina. I am not an
ophthalmologist, however, a few of my relatives had detached retinas so I
made a point of reading up on the subject. Briefly, from what I have
read, detached retinas are a result of the thinning of the part of the
eyeball to which the retina is attached. This usually occurs in acutely
near-sighted individuals because their eyeballs are more elongated or
oblong in shape, thus causing physical stress on that part of the
eyeball. I guess it would be akin to putting a piece of scotch tape on a
partially filled balloon, then blowing the ballon up to its fullest
extent. In the case of my relatives, the operation to reverse this
involved, interestingly enough, "welding" the retina back in place with
lasers.

That's my simplified, and possibly incorrect interpretation of the
materal that I have read with respect to detatched retinas. No doubt
there is an ophthalmologist in the crowd who can provide a better
explanation.

Now that a few of you have come out of the closet, I might as well admit
here that I too, have, on a few occasions, inadvertently looked directly
into the sun with my sextant and with a 6X scope. It is a rather careless
thing to do so I was loath to broadcast it. But there you have it. In any
event, I have suffered no ill effects and a recent eye examination
confirmed that my eyes are in perfect condition (except now I need
reading glasses - growing old sucks).

I tend to agree with previous posters that humans are attuned to shying
away from looking directly at the sun and if we do by accident, it is
probably for only a millisecond before our protective instincts kick in.
(Ok, while we're at it, I've also caught site of a welder's flash too;
despite being told a billion times to look away. Might as well tell me
not to push that button).

My two bits' worth.


>In one of Tristan Jones' sagas I seem to recall he suffered a detached
>retina following an attempt at taking a noon sight without shades.
Somewhere
>off the Amazon delta although he thought he was somewhere else at the
time?
>Ted Gerrard
>tedgerrard@onetel.com

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