Archive for April 2020

NGC 188 – A Very Faint and Difficult Open Cluster, and so Close to Polaris

April 30, 2020

AUGUST 2010 OBSERVERS CHALLENGE – NGC-188 

 

The Questar 3.5-Inch Telescope Story, Vernonscope/Brandon Eyepieces and a Meade ETX 90 Astro

April 25, 2020

     Questar Telescopes (Maksutov-Cassegrain) have been built in New Hope, Pennsylvania since 1950.  Questar has chosen Brandon eyepieces for many years, which are also made in the USA.   https://www.questar-corp.com/

     Brandon eyepieces are optimized for telescopes with a focal ratio of f/7 or greater.   https://043a19c.netsolhost.com/

     The following are some photographs of a friends 3.5-inch Duplex.    

DSCF5015

DSCF5012    

     During the early 50’s, Cave Optical in Long Beach, California, manufactured the 3.5-inch mirrors.

    Questar advertised on the back of the front cover page of “Sky & Telescope Magazine” for decades!

A challenge to Questar?   

     In 1996, Meade Instruments Corporation, introduced the Meade ETX 90mm Astro.  This telescope was designed to be an economy Questar.  Mostly constructed of plastic, but with all the emphasis on the optics.   

     At that time, Meade was manufacturing the ETX, as well as most all of their higher-end telescopes in Irvine, California.     

     I purchased an ETX 90 the following year (1997) for use as a very portable telescope, to observe deep-sky objects within its grasp.  It served that purpose well.  The telescope had very good optics and would easily exceed Dawes’ Limit on double stars on a night with good to excellent seeing. 

     Dawes Limit:  4.56/A (A is aperture in inches) for two equal stars of about 6th magnitude.   

https://www.astronomics.com/info-library/astronomical-terms/dawes-limit/                                                                                                                                                                                               

     However, when considering fit, finish, cosmetics and ease of use, the ETX “cannot” even remotely compare to the “much” more expensive and precision Questar.  

     The 3.5-inch Questar continues to have its place in astronomy, despite most amateurs of today wanting larger and larger telescopes, but how many telescope companies do you know that have been in business since 1950?

      And from their longtime advertisement in “S&T” the following was said:   “Questar, The World’s Finest, Most Versatile Telescope”

     This must be true, to have survived in the ever-changing world of amateur astronomy equipment for 70 years.  (1950 – 2020)  

      I wrote the following story back in (2012) and it still receives views, even to this day.    Roger Ivester

https://rogerivester.com/2012/02/02/questar-a-high-precision-3-5-inch-telescope/

M85 and NGC 4394: Galaxies in Coma Berenices: Observer’s Challenge Report for May 2020: #136

April 22, 2020

MONTHLY OBSERVER’S CHALLENGE

Compiled by:

Roger Ivester, North Carolina

&

Sue French, New York

May 2020

Report #136 

M85 and NGC 4394:  Galaxies in Coma Berenices 

May 2020 OBSERVERS CHALLENGE _M85 and NGC 4394