All Observer’s Challenge Reports to-date:

https://rogerivester.com/category/observers-challenge-reports-complete/

      Walter Scott Houston, most often used a 4-inch Clark refractor for his observations of deep-sky objects while writing the monthly “Deep-Sky Wonder’s” column in “Sky & Telescope Magazine” for 46 years until his death in December, 1993.  

     When Sue French picked up DSW’s, she seemed to favor the use of a 105mm refractor for many observations over her twenty years writing the column.  

      I purchased my 102mm f/9.8 refractor in 1997, and have enjoyed using this scope over the years.  It provides for a nice velvety black background with excellent contrast of faint deep-sky objects within its reach.  

      On nights of good seeing, it will easily exceed Dawes Limit:  https://www.astronomics.com/info-library/astronomical-terms/dawes-limit/  

      Double and multiple stars have always been of interest to me, and I’ve observed hundreds of close double and multiple stars over the years with this telescope.  

The value of a correct image diagonal:

I’m now using a correct image 90º diagonal.  The view through a standard 90º diagonal, whether using a refractor, Schmidt-Cassegrain or Maksutov-Cassegrain makes it impossible (at least for me) to sketch a deep-sky object, scientifically correct. I like to make my sketches as they are truly oriented in the sky, with north at the top and west to the right on my sketch card.    

https://www.telescope.com/The-Advantages-of-Observing-with-Correct-Image-Diagonal/p/106656.uts

 

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