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    Re: Looking at the Sun
    From: Ken Muldrew
    Date: 2009 Jun 19, 22:31 -0600
    From:                         <frankreed{at}HistoricalAtlas.com>

    > Just as a general un-scientific survey, how many of you have caught a
    > quick glimpse of the Sun through a sextant telescope? How long did it
    > take for the spots to go away.

    I've seen a couple of flashes through the 5x scope on my sextant. The spots probably lasted a minute or two, I don't remember well enough to guess better than that. There was no later pain due to these brief glimpses. My sextant has a sunshade in front of the telescope and even though it's painted black, I can't count the number of times I've seen the sun reflected of this shade and thought (just for a second) that I had gotten the full sun through the scope.

    I have had snow blindness a few times and a couple of welder's flashes (only one of which resulted in pain). I don't think you will do any harm to your eyes without knowing about it. It really does hurt like the devil (it feels like you have sand under your eyelids). So the fellow who was worried about his 90 year old shades is quite safe if he has been using them for some time without effect. It's really just the first time you use your shades that you take some risk.

    Like Frank, I have stared at the setting sun many times. The rule of thumb is that if it's bright enough to make you want to look away, then look away.

    Ken Muldrew.

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