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CN Reports

Observer's Handbook - 2019 Updated Preview

Sep 23 2018 11:14 AM | Tom T in CN Reports

Tom Trusock and Denise Moser takes a look at the upcoming 2019 edition of the RASC Observer's Handbook.

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Observer's Handbook 2016

Dec 15 2015 09:39 PM | Tom T in CN Reports

Tom Trusock takes a look at the 2016 edition of the RASC Observer's Handbook.

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Thermal Modeling and Athermalization in Telescope Optical Design

Dec 09 2014 03:16 PM | Mike I. Jones in Technical Reports

Telescopes are typically stored and operated over a wide range of temperatures. Changing temperatures and extreme temperature ranges affect nearly all materials used in constructing telescopes, as well as the optical properties of the air in the immediate vicinity. This article discusses the two principle effects of temperature on telescope materials: (1) changes in optical and structural material dimensions with temperature, and (2) changes in optical glass refractive index with temperature. These two temperature-dependent material properties usually combine to negatively affect optical performance in refractive and catadioptric systems if not compensated for, and system optimization must account for these properties in the design phase to minimize temperature effects on telescope performance.

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A. Jaegers Optical Corporation--A personal recollection

Nov 22 2014 02:37 PM | Scott in NC in Other Reports

A. Jaegers Optical Corporation--A personal recollection Stephen L. Nightingale For many teenagers in the 1960’s, an after-school or summer job meant...MacDonald’s! As a teenage amateur astronomer and telescope nut, I had the perfect job--working for Al Jaegers at A. Jaegers Optical Corporation from 1968 to 1970.

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2015 RASC Observer's Guide

Dec 26 2012 04:18 AM | CN_Admin in CN Reports

Join us as Tom Trusock takes a look at the 107th version of the venerable RASC Observer's Handbook.

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Great Lakes Star Gaze - 2003 - First Annual

Mar 29 2011 06:34 AM | CN_Admin in Other Reports

This month marked a new era for Michigan: the return of its annual statewide star party. Not since SMURFS folded have all Michigan amateurs had an event they could truly call their own

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StarLab: A Portable Planatarium

Mar 29 2011 06:23 AM | CN_Admin in Other Reports

Imagine that you have the ability to walk into a room at anytime and see the night sky. Imagine having your own personal planetarium. Now imagine that it is portable, and will easily fit in

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Kufeld Telrad Vs. Rigel Quickfinder

Mar 29 2011 05:24 AM | David Knisely in Accessories Reports

I had purchased a QuickFinder to put on the front of the dewcap of my 100mm f/6 refractor, as I was occasionally having trouble getting to the new "correct-image" right angle optical finder I had installed earlier

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Readers Choice: Gear of the Year 2010

Feb 18 2011 08:41 AM | CN_Admin in CN Reports

Nominated by you, chosen by you - here's the top gear of 2010...

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CN Reports Review: Orion SkyQuest XX14i

Jan 12 2011 10:58 AM | David Knisely in New CN Reports in [!monthname!]

The Orion SkyQuest XX14i Truss-tube Dobsonian is a fairly nice large aperture instrument for the amateur who needs something a bit bigger than what is usually offered by the solid tubed telescopes.

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