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Old 06-09-2018, 12:08 PM
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Wavytone is offline
Join Date: Jul 2008
Location: Killara, Sydney
Posts: 4,147
IMHO No need for a laser collimator because a Newtonian provides a really good way using the Poisson spot, as follows:

Choose a bright star near the zenith and use any medium power eyepiece, defocus a tad and twiddle knobs till the scope is close to aligned, ie you see concentric circles around a central dark spot (the shadow of the secondary).

Now insert a cheap high-power eyepiece - 4mm would do nicely. With the star slightly defocussed you should see bright rings (the star) with a dark centre.

If you look very closely you should see the Poisson spot - a bright dot near the centre of the dark shadow and the bright rings. When you get this centred with respect to the bright rings the scope is aligned.

Note this is quite sensitive to change - just cracking the alignment screws will move the Poisson spot noticably.
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Old 06-09-2018, 02:38 PM
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Oh, I See You Are Empty!

OICURMT is offline
Join Date: Apr 2010
Location: Laramie, WY - United States of America
Posts: 1,491
Solar filter looks good. Check it every time you use it by holding up to a light source and checking for pinholes.

You can cover the pinholes with a black marker or small pieces of black tape.

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