Over the years, we’ve seen conversational topics in online amateur circles that repeatedly crop up concerning the definition of apochromatic refractor, triplet vs. doublet design, and how glass designation might define performance. We expect these questions to continue to appear as new amateurs discover the hobby. So bookmark this blog post because here you’ll find notes on Tele Vue’s philosophy and build practices concerning our telescope line of 100% APO refractors.
Our very portable Tele Vue-76 APO refractor has been popular with eclipse-chasers as well as with users that cross over into spotting and birding. With the popularity of small and powerful dedicated imaging cameras, the performance of the Tele Vue-76 is getting noticed by deep-sky imagers on the go. Case in point, Diego Cartes Saavedra is producing outstanding deep-space images from various locations in the southern-hemisphere with this scope. All his images in this blog post were taken from July through November 2018.
Diego’s study of the Tarantula Nebula and surrounding region in the Large Magellanic Cloud examines the area imaged through different filters. The first image is a monochrome version taken in Hydrogen-α light.
All Tele Vue telescopes now come standard as optical tube assemblies (OTA) that can be turned into “complete” units with optional, customized accessory packages. The package costs can be substantially less than pricing each component individually. This blog takes you through the changes for the Tele Vue-60, Tele Vue-76, and Tele Vue-85 models. Accessory packages for the larger scopes will be covered in a future blog.
After the penumbral eclipse of the new moon on February 11th, we have an Annular Solar Eclipse just a half-lunar-cycle later. Unlike the lunar eclipse, this one will need proper filtering to observe naked eye or through scopes. The eclipse is annular because only the central part of the sun is obscured, leaving a thin ring (annulus) of light around the edge. This happens because the moon’s orbit brings it closer and further from the earth — so its angular size from earth can vary from 29.4-arc-minutes to 33.5-arc-minutes. The size of the sun hardly varies from 32-arc-minutes due to the small eccentricity of the earth’s orbit. Thus, the moon can appear to be bigger or smaller than the sun according to the circumstances. Continue reading “Countdown: Annular Solar Eclipse Feb. 26, 2017”