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Paul,
Actually the reading lens ("microscope") on the SNO-T can be adjusted
for reading the scale without glasses. I am not sure in what limits,
but it works for me. Even at night, without a flashlight.
My personal problem is that I have to read the watch first.
And most wrist watches I cannot read reliably without glasses:-(

Some authority in Cel Nav, I don't remember who exactly, recommended
to use young sailors (midshipmen, even hands) for taking altitudes,
and the experienced navigator only reads the scale, does reduction
and all math and plots:-)

Alex.


> Bruce Bauer writes – The Sextant Handbook – “What many people end up
> doing is taking the sight bare eyed with the scope adjusted to compensate
> for vision defects and then putting on the glasses for reading time and
> altitude.”
> My problem is that I can’t do that adjustment using my SNO-T sextant. I
> am short sighted – about minus 8 dioptres nowadays – and it isn’t
> possible to shorten the Galilean scope enough to get a clear image without
>  glasses. Thus my problem is reversed to that described by Bruce Bauer. I
> can read and write both with and without glasses but I can’t take sights
> without  them.
> The solution is so obvious and simple that it must have been tried before.
> A compensating lens is gently pressed into the rubber eye shield. It is a
> lens from an old pair of glasses, cut circular, diameter 28 mm.
> See attachments!
> I am of course aware of that this is possible because of the design of
> this particular eyes shield and perhaps not optimal from an opticians
> point of view - but for me better than a sextant / glasses combination.
> As to taking off  / putting on glasses when using binoculars or taking
> sextant sights I just push them, the glasses, up above my eyebrows. A
> slight grimace and they are back on my nose. And it helps that I always
> have a glasses strap when aboard.
>
> Paul Werner
>
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> Attached File: http://fer3.com/arc/imgx/A--Scope-illustration.JPG
> Attached File: http://fer3.com/arc/imgx/B--Scope--shield-lens.JPG
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> : http://fer3.com/arc/m2.aspx?i=127314
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