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I just purchased a powerseeker 114q by Celestron. This is my very first telescope. I believe I assembled it correctly however I can't see anything out of it. Well I can see a small corner of an image. When I look at the reflector in the back of the telescope, I can see a small part of my face. It is the same when I look through the lens. I only can see a small piece of the sky. I think its the sky anyway. The rest is completely black. All of the lens caps are off. I followed the setup directions down to the letter. Can someone please help.

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  • $\begingroup$ Probably not an appropriate question for this site, but did you go through the collimation step? This involves removing the eyepiece and looking at the secondary mirror, while adjusting screws and knobs at the back of the scope. $\endgroup$ – Russell Borogove Jan 22 '15 at 6:00
  • $\begingroup$ Misaligned secondary mirror maybe? $\endgroup$ – asawyer Jan 22 '15 at 14:26
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The PowerSeeker will come with a manual on collimation of the mirrors. As the light entering the telescope hits the primary lens, the light reflects and compresses onto the secondary mirror, in turn reflects and compresses the light onto the eyepiece. When the mirrors are misaligned, the light rays aren't correctly focused onto a point where they are projected through the eyepiece, as such like turning a mirror around your point of view, you will not see directly behind yourself but rather an angle.

This is what is happening even as you look directly down the tube at the primary mirror; if it is not directly facing you, you will not see your face (perhaps part of it) and you will see the sides inside the tube.

There are various method for collimation, personally I use a laser collimater and a barlow to increase the sensitivity. The methods are dependent on what you have available however, you don't need any additional tools to collimate apart from the telescope itself.

The PowerSeeker does not have a central marking on it's primary mirror to indicate the center of the mirror, if you are confident in disassembling the rear of the tube you can remove the mirror and measure the central point and mark it. If not, you will not get a collimation as precise, however generally it will suffice until you gain experience.

When looking through an empty eyepiece barrel, if the primary mirror doesn't appear central in the view, as in you can see the whole mirror and the spacing around the mirror is equal, then the secondary mirror needs adjustment. In the same respect, if the central point of the primary mirror does not line up in the center of view, the primary mirror needs adjusting. You do not need to get the line of sight with the primary mirror 100%, typically users of telescopes may use a star itself for collimation; too lengthy to explain however when viewing a star outside of focus (best to use largest magnification possible/smallest diameter eyepiece) the airy disk of a star will appear distorted to one side, centralizing that airy disk will provide an accurate collimation.

Further information will be available in the manual, or there are a many websites to help finetune collimation. If you need further advice just edit your above post or post a comment.

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