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Telescope use
Hi guys, merry Christmas. I haven't posted for a while now because of my exams coming up, but before any updates I've just got to ask this question. I've been given a telescope that I'm excited about for Christmas and am wondering what anyone can tell me about the effects this can have on the eyes and how to avoid straining them when using it. For example, I've read that it's best to have it focused to infinity because the relaxed eye is focused to infinity, but I'm not sure if that applies to myopic people who aren't wearing corrective lenses. I don't know much at all about how either eyes or telescopes work, you see. Thanks! Smile
Dear Opticfog,

If you are nearsighted you can not set the telescope for "infinity". ???

But what you will do (in daylight) is to look at a distant object through
the telescope, and move the eye-piece in or out, until the distant
object "clears" -- to your satisfaction.

While difficult to describe, you move the eye-piece out till it is blurred,
and then move in "in" until best "relaxed" vision is preceived by you. Smile

Once you get comfortable in day light, then practice on the moon.

Astronomy is one of my hobbies. Smile


Thanks for the advice otis! Looks like I'll be lucky to see even the moon tonight, we've the cloudiest sky I remember having over here. :Smile

I'll just admire and polish it. Wink
As with anything, don't make yourself uncomfortable while you're using it. If you hunch over, stiffen your neck, and close your other eye, you're most likely straining the eye you're using. Better to cover the other eye with your hand or a patch or something, even though it seems like a little trouble. And the best way to ensure your vision doesn't suffer while doing this for long periods is to frequently take brief breaks to look around you and do a self check to make sure you aren't making yourself tense and losing your focus.

Site Administrator

"Half of our funny, heathen lives, we are bent double to gather things we have tossed away." - George Meredith
Hi Optifog, Merry Christmas to you, too.

If you're interested, Dr. Bates walks you through how to obtain telescopic vision with the naked eye in this 1921 medical article:

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I think it would be so cool to have telescopic and microscopic eye focusing power! ;D
Hey Optifrog,
that's really cool, I always wanted a telescope.
I wouldn't worry, I use a microscope very often and it doesn't cause me much strain. Don't worry about the infinity focus, just make sure you focus it well and don't make the image blurry (blur = strain). Also, put the eyepiece to 0 focus (to make both eyes see with the same level of focus. Having it otherwise usually strains my eyes.


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