* Astronomy

Collimating a telescope is lining up its optical components (lenses, mirrors, prisms, eyepieces) in their proper positions. This should be accurately done, or else the image quality will suffer.
Different telescope types, like Newtonian, Schmidt-Cassegrain, or refractors all need good collimation. However, they have quite different optical components, and here I will only talk about Newtonian telescopes, the simplest mirror telescopes.
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telescope collimation - how to collimate telescope

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Newtonian Collimation

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Collimating a Newtonian Telescope

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This guide focuses on the optical alignment, or Collimation, of Newtonian telescopes. The guide is based on a SkyWatcher Explorer 200, however the principals are the same for any telescope of Newtonian design, including Dobsonian.
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