December 2018 – Tele Vue Optics

Tele Vue Scope Renaissance! (Part I)

Tele Vue Renaissance brass telescope (built 1984-1993) was the first Nagler-Petzval type lens design to go into wide-spread production. With its solid brass tube, its classic look is timeless.

Restoring a Storied Scope

A customer recently called because his vintage Tele Vue Renaissance telescope needed some tender-loving care. The Renaissance was our second model, put on the market after the 1981 “Multi-Purpose Telescope” (MPT). The customer’s scope was built in 1985 and is from the initial production design with a bolt-on focuser. After discussing the obvious issues that needed addressing and our evaluation process, he decided it would be worth it to him for us to have a look at the scope.

When we received the scope, the most obvious troubling issue was the focuser. It was unusable. The pinion shaft was badly bent and two of the three teflon runners supporting the draw-tube along its travel were missing. The outer surface of the objective showed years of grime, and all of the brass components were heavily oxidized. The optics, however, were only slightly mis-aligned, producing a mildly flaired star shape at high power, but the image was still serviceable for terrestrial and deep sky viewing. Sadly, after a complete optical and mechanical inspection, we concluded that it just wasn’t worth the effort and expense to revive the telescope. That, however, was not our customer’s conclusion.

He gave us the go-ahead and we proceeded to give his 1985, brass Tele Vue Renaissance a new lease on life. A “renaissance” for this Renaissance if you will!

Left: The brass telescope tube in need of polishing. Right: tube after machine and hand polishing.

Continue reading “Tele Vue Scope Renaissance! (Part I)”

Tele Vue Scope Renaissance! (Part II)

This post is about maintaining a brass Renaissance and matching Gibraltar mount. For the post on restoring a brass Renaissance, please see our companion blog post:

Tele Vue Scope Renaissance! (Part I)

Vic Bradford’s brass Renaissance 102 on matching Gibraltar mount stands in front of an antique pie safe. Images courtesy of Vic Bradford.

Vic Bradford has owned a brass Renaissance telescope since 2006, about 20 years after he first saw Al Nagler show one at a Riverside Star Party. He regrets not owning one sooner as “the scope uniquely merges the beauty of form and function”. We’ve reprinted some excerpts below from a treatise he sent us on caring for the brass on his Renaissance telescope and brass fittings on his matching Tele Vue Gibraltar mount. He offers a caveat to the reader: “you may find these suggestions overkill and much can be said for simply leaving brass alone so it can develop a nice patina. Like any other fine equipment, though, it benefits from good care and research.”

These instructions are for cleaning and polishing brass lacking a clear-coating. Following these instructions will ruin your coating.

Continue reading “Tele Vue Scope Renaissance! (Part II)”

Happy Holidays from Comet 46P/Wirtanen

At only 30-lunar distances from Earth, Comet 46P/Wirtanen brightened to magnitude 3.6 as it brushed by our planet on December 16th — just 4-days after perihelion (closest to sun). The anticipation of this close pass-by engaged the attention of many amateurs that observed and imaged this “dirty-snowball” in the weeks leading up to the fly-by. But the most iconic image of this comet’s apparition was made two-weeks before its closest approach to Earth.

46P/Wirtanen, Moon Size Comparison by flickr user Mike Broussard. All rights reserved. Used by permission. Imaged with Tele Vue-85 APO and Tele Vue TRF-2008 0.8x Reducer/Flattener for f/5.6. Camera used was Canon T3 with IDAS-LPS (Light Pollution) filter. Exposure at ISO 3200 for 40×120 sec. Image taken Dec 2, 2018 at 03:05 UT.

Continue reading “Happy Holidays from Comet 46P/Wirtanen”

Tele Vue’s 2018!

Rho Ophiuchi & Friends by AstroBin user David Augros. Copyright David Augros. Used by permission. NP101is APO refractor plus Large Field Corrector (LCL-1069) with Lumicon Deep Sky 2″ filter into modified Canon EOS 6D DSLR.

It’s hard to believe that our blog has been posting articles for two solid years already. We didn’t note it at the time, but our post “odometer” rolled past 100 this October. Our 101_st post was Tele Vue-NP101is Imaging the Skies of Rhode Island! It featured David Augros’ images from a dark-site on Rhode Island with a Tele Vue-NP101is using our Large Field Corrector and modified Canon EOS 6D DSLR. He chose that scope because it offered “a nice balance between a generous wide field and fine details in my final images.”

Continue reading “Tele Vue’s 2018!”

Tele Vue-76: Imaging the Southern Hemisphere

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.