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    Re: Eyesight dangers using telescopes
    From: Peter Fogg
    Date: 2009 Jun 30, 13:08 +1000
    Ken Gebhart wrote:

    Now that this thread is coming to a close, can the following
    questions be answered?

    1.  Does normal sextant use, even by a neophyte, pose any significant
    risk of eye injury?  (I use the term significant, because we all know
    we are damaged by cosmic radiation, UV, second hand smoke, lead, beer
    and any number of other things with which we have daily contact.  I
    am not concerned with this level of danger.)

    2.  Does the risk of eye injury increase with the addition of a
    magnifying scope?

    I hope (by now) that each question can be answered with a simple yes
    or no, with no further elaboration.
    As if its at all likely that anyone is going to answer: "with a simple yes
    or no, with no further elaboration" !
    I think that anyone who uses a sextant for observing the sun would have to agree that this use DOES lead to an increased risk of eye damage, since apart from this use most people have no need to look towards the sun at all, particularly when it is well above the horizon.  I guess that anyone who has used a sextant with the sun has had the occasional flash of sunlight directly into the eyes, which is not desirable.
    I also think that whether its "significant" as Ken Gebhart has defined this term will vary with individual perception as to the risk, with or without scope.

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