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Telescope issues.

Need our opinion on a telescope Optics Planet has on sale, go ahead and ask! Post some hints and tips on various telescope brands and configuration.

Telescope issues.

Postby esa20 on Mon Dec 29, 2008 6:57 pm

I just received a bushnell model 78 9669 scope. I tried to look at some things this evening, but the problem is, I can see images, but they are obscured by a black dot and/or a black line.
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Postby Jne_K on Tue Dec 30, 2008 6:24 am


That's called secondary obstruction - the shadow of the secondary (front) mirror and the lines are the shadows of the spider (vanes) that hold it in place. Under some lighting conditions, you will see these, but under most conditions you will not. Ignore it - it has no significant effect on your scope for astronomy. ALL reflectors have this.
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