Explore Scientific AR 102
Feb 09 2016 10:10 AM by phxbird
Review: davejlec's Paralellogram Mount
Feb 08 2016 11:26 AM by tlriedel
Annals of the Deep Sky, Volumes One and Two
Feb 08 2016 10:03 AM by twatson
Discovery 17.5” Split Tube Dobsonian Telescope
Feb 07 2016 09:20 AM by clay1022
REVIEW OF SUMERIAN OPTICS ALKAID 16” TRAVEL SCOPE
Nov 26 2015 05:38 AM by alexvh
Astrotrac TP3065 Pier Review
Nov 20 2015 08:03 AM by James Waters
Apo-tmosphere: Gutekunst ADC Review
Sep 23 2015 11:18 AM by pbsastro
Optolong LRGB Filter Testing and Comparison wit...
Sep 22 2015 01:41 PM by turbo399
Most of us have had the desire to take a break from using the average telescope with its relatively high power and concomitant narrow field of view and difficulty in finding targets. The so- called rich field telescope or large binoculars seem to fill the bill with their low power and wide fields. The question then becomes how to mount the thing for comfortable, extended viewing.
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.
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.
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