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Night Vision Astronomy 2015: Three Perspectives

Jan 06 2016 05:15 PM | The Ardent in Articles

Night Vision technology is a powerful tool to enhance observing. Like any observing method, it had its advantages and drawbacks. Three Cloudy Nights members offer their experience.

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There's a Catch!

Nov 25 2015 12:26 PM | GeezerGazer in Articles

For at least 10 years, observers have complained in forums about eyepiece barrel undercuts causing various problems, but especially catches. Because of my own experiences with catches occurring during insertion or extraction of an eyepiece when used with an adapter, I decided to do some investigation as to why. Catches, I found, are not a one sided issue.

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Blue Skies, Red Sunsets & Company: Part 5 -...

Nov 24 2015 11:08 AM | Snickersnee in Articles

If you watch enough sunsets, you'll eventually see one where, just as the last sliver of sun slips away, it turns green or reappears for an instant as a flash of greenish light. Congratulate yourself - you have just seen the famous green flash!

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Notes on the Construction of an Oiled Contact D...

Nov 17 2015 04:09 PM | mrtoad in Articles

This is a description of my adventures with the fabrication of a 6” f/15 oiled achromat.It is assumed you will know all about grinding, polishing and figuring. It will discuss some problems I ran into and what I did to solve them in the easiest and most practical way, as well as things to watch out for. This is not a step by step description of the making of a refracting objective let alone the complete telescope.

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Beefing Up Hollow Aluminum Tripod Legs

Oct 12 2015 09:51 AM | CollinofAlabama in Articles

If you’re mount setup seems a bit too wobbly in the wind, well this West Texan might have the answer. This will not make a woefully inadequate mount suddenly fine, but it should help someone whose mount is almost capable enough, but not quite. People write on CN that this is self-evident, and after reading this article you may agree, but I like pointing out the obvious. Hope someone finds it edifying.

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The Amazing HyperStar: A Guide to Optimize Perf...

Sep 29 2015 08:36 AM | jhayes_tucson in Articles

In spite of its advantages, the HyperStar system is not quite as easy to use as a modern day apochromatic astrograph and many users have trouble achieving good results. The problem generally isn’t with the optical system; it’s often the result of not knowing how to properly align and use the system. Although Starizona provides user instructions for aligning and using the HyperStar system, the manual is fairly basic. This guide is intended to provide additional information to get the best performance out of the HypeStar System.

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Blue Skies, Red Sunsets & Company: Part4 -...

Sep 24 2015 02:49 PM | Snickersnee in Articles

Refraction changes the shape of the setting sun. The oval shape most commonly seen is just the simplest example. Much more complex changes in appearance can occur because of refraction and these are called mirages.

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Revisiting Celestron’s Compustar: The Grand Dad...

Sep 23 2015 09:25 AM | orion61 in Articles

I can’t tell you how many negative things I had heard about them, but in their day everybody wanted one. They were the first, each one was removed from the factory, had the electronics added on and shipped back for delivery.

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Introduction to Stellar Spectroscopy

Sep 05 2015 04:56 AM | rekokich in Articles

In 1814 Bavarian optician Joseph Fraunhofer invented the modern slit spectroscope. He demonstrated bright emission lines when burning various elements, as well as numerous dark absorption lines in the spectrum of sunlight which are in his honor still called Fraunhofer lines. In 1821 he improved the diffraction grating first invented in 1785 by American astronomer David Rittenhouse. Fraunhofer then founded stellar spectroscopy by showing that spectra of several bright stars differed from each other and from the spectrum of the Sun.

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DSLR Astrophotography Untracked

Aug 15 2015 01:22 PM | project nightflight in Articles

With DSLRs and standard camera lenses astrophotography is on the verge of a new epoch, where tracking is no longer absolutely mandatory. When we heard about the technique described in this article, we immediately wanted to give it a try. It allows any stargazer using a modern DSLR to capture colorful, noise-free images of deep-sky objects, without an equatorial mount or tracking device needed.

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