Bushnell NorthStar 78-8846 (675 x 114mm) Telescope Logo
Posted on Jul 08, 2008

Dot in view

We have a Bushnell 78-8846 North star telescope. We are now seeing a black dot and a straight line to one side when looking through the telescope. How do we fix this problem? The Bushnell manual has no info.

  • Anonymous May 11, 2010

    ????? I am having the same problem. The eyepiece I am using is 22 mm focal lengh?????

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  • Posted on Nov 05, 2009
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Sounds like a collimation problem!! do you know how to collimate the optics?

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There is a general rule of thumb that states you can expect to view 50x per inch of aperture. Your telescope has roughly 5" of aperture. 5 times 50 equals a maximum of 250x. However, this is a guideline. On bad nights like I had you'll never reach that 250x since objects will appear blurry or unstable. On good nights, you can exceed this.

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Hello !
I had the same trouble. It's normal, you just have to put a lens to straight the image (it's use for terrestrial view).
XXX
Pierre
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