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View Orientation in Newtonian Reflector Telescope

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#1 bluesteel

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Posted 02 April 2013 - 09:08 PM

This would be the last piece of the puzzle for me on deciding the type of telescope that I would like to eventually acquire. From what I have read, the view is upside down when looking through a Newtonian reflector with a primary and secondary mirror setup versus looking through binoculars. However, doesn't the upside down-ness have to do also with the position of the eye-piece? In this sense, if I were to look at an object at around 45 degrees from the horizon, with the eye piece pointing at the zenith, would the image orientation be right side up? What about if the eye piece was pointing at the ground with the same 45 degree orientation?
Thank you for your replies!

#2 GlennLeDrew

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Posted 02 April 2013 - 09:26 PM

Indeed, the eyepiece position has a bearing. Ultimately, as the telescope is pointed over various parts of the sky, the orientation of your eye with respect to the OTA is the factor which controls image orientation. It's always varying, unless you can contrive to effectively strap yourself to the tube like a Koala Bear and thereby keep your eye fixed in place.

The main thing is that the image is not mirror reversed, as happens with refractors, Cats and Maks when used with diagonals.

#3 bluesteel

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Posted 02 April 2013 - 10:19 PM

Thank you.
Koala bear viewing, I like it. Sounds much more comfortable than sitting... but that would take one heck of a mount!

#4 lamplight

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Posted 03 April 2013 - 08:58 AM

Still learning. Great question blue steel.

#5 Paco_Grande

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Posted 03 April 2013 - 12:12 PM

The image is reflected upside down no matter how the EP is oriented.

#6 GlennLeDrew

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Posted 03 April 2013 - 12:18 PM

One way to obtain an upright image is to orient the eyepiece vertically and stand with your back to the target (getting your body out of the way, of course.) This would be the kind of thing to do at a star party during the day, gazing across the field at your neighbours.






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