Why are objects tilted when I look through the eyepiece on my telescope?

6 Comments

1. onegater says:

   June 6, 2010 at 12:45 am

   Your head might be tilted when you look through the eyepiece.
2. Simmi says:

   June 6, 2010 at 12:49 am

   maybe it isnt alligned correct(and they look that way because of deffraction)
3. RickB says:

   June 6, 2010 at 1:27 am

   First, the objective element (which is either the lens in the front or the big mirror in the back, depending on what kind of telescope you have) will cause the image to rotate by 180° — that’s just the way lenses/mirrors work.

   Then, before it reaches your eye, the light is reflected at right angle by a mirror or prism (so it comes out perpendicular to the tube). This adds an additional tilt to it, whose angle depends on the angle of the mirror or prism (which tends to change as you re-orient the telescope to look at different parts of the sky).
4. screaming monk says:

   June 6, 2010 at 2:21 am

   Is it possible that your diagonal is ’swung around’ and oriented that way! It would be like if I lifted one side of my monitor.
5. Geoff G says:

   June 6, 2010 at 2:34 am

   Yours is a Dob, if I remember correctly. If the eyepiece were located on top of the tube or 90° away from that, on the side, the image would be exactly inverted. But since your eyepiece is probably around 45° away from the top, the image is rotated by that amount. Since there’s no right way up in space, we all just get used to the orientation. At least with a Dob, the angle is always the same; on an equatorial mount, a Newtonian’s eyepiece orientation is all over the place!