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CN Reports


The Astronomer at the Museum: Max Ernst and Wilhelm Tempel

Apr 01 2020 07:51 AM | Larry F in CN Reports

One of the great things about astronomy is how it connects you to so many spheres of human thought and activity, both scientific and cultural. You never know when some unknown link is suddenly revealed, and you learn something remarkable. My latest “astrocultural” discovery was at the Museum of Modern Art, which in the fall of 2017 exhibited a large selection of its extensive holdings of works by the prolific German surrealist artist Max Ernst (1891-1976).

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Deep Sky Lucky Imaging

Jan 14 2020 01:53 PM | CygnusBob in CN Reports

Amateur astronomers have been using lucky imaging for planetary targets with great success. The basic strategy is to obtain a large number of short exposure images in order to “freeze” the turbulence and then select the sharpest images for alignment and integration. Short exposures are valuable because the biggest effect of turbulence for small telescopes is image jitter. For long exposures, the image jitter gets averaged out, just generating a blurred image. The problem with doing this with deep sky objects is that the number of photons collected in a 1/60 of a second is rather small in most cases. This makes it hard to determine an image shift accurately. However lucky imaging can still help sharpen DSO imagery.

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Optimal Filtering for Deep Sky Lucky Imaging

Dec 15 2019 12:30 PM | CygnusBob in CN Reports

A paper that describes a method of noise reduction for DSO imagery that I have invented for Deep Sky Lucky Imaging. I am Dr. Robert Majewski, a retired engineer living in Las Vegas. I have M.S. and Ph.D. degrees in Physics from the University of Illinois. My career involved testing and calibrating a number of imaging electro-optical systems at the Hughes Aircraft Company and Raytheon Missile Systems. My hobbies include high resolution planetary imaging, exo-planet transits and deep sky imaging.

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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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