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Just got a Celestron Astromaster 114eq as a christmas present and I have tried setting up the Star Pointer in the daylight. I did not use the red dot method as in the instruction manual, instead, I tried to do this by viewing a object through the main scope (placing the object in the center of the main scope) and then I made some slight adjustments to the Star Pointer finder scope aligning both circle and dots on the finder scope using the two adjustment screws.

This seems to work fine and finds the targets quite well,but when it turns dark and I turn on the the red dot in the finder scope and aim at a star I have yet to manage to focus in on it. Should the method I used to set up the scope finder or do I need to set up the scope finder in the dark?

Any help would be appreciated.

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  • $\begingroup$ Per the guidelines, this question is absolutely on-topic here. $\endgroup$ – Donald.McLean Jan 1 '17 at 14:24
  • $\begingroup$ when you say " I have yet to manage to focus in on it", do you mean that you can't see any star, or you can't get the star in focus? Make sure to use the 20mm eyepiece intially. $\endgroup$ – Dr Chuck Jan 1 '17 at 14:45
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For an astronomical object, a 1000 mm focal length objective forms an image 1000 mm away. However, the image of a terrestrial object focuses farther out: 1010 mm for a target 100 m away, 1020 mm for a target 50 m away. When switching from a terrestrial target to an astronomical one, the eyepiece must move closer in.

Aligning the finder on a terrestrial target is bound to produce some parallax error. After focusing the telescope on a bright planet or the Moon, aim the telescope at Polaris and fine-tune the finder.

Finally, even with good finder alignment, sometimes you will have to sweep to locate your target. It gets easier with practice.

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