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20 Inch Dobsonian Telescope

Looking Through a 20 Inch Dobsonian Telescope!

20 Inch Dobsonian Telescope

A photo of me looking through a 20″ Dobsonian Telescope.

A Million Dollar View

A member of my Local Astronomy Club in Niagara (RASC – Niagara Centre) owns a massive 20 Inch Dobsonian Telescope that he will often bring out to our Observatory Site in the summer.  This experience is always a real treat, as the views through this giant “Dob” are incredible.  

This telescope is so huge, that you must climb a ladder to look through the eyepiece when it is pointing at most targets overhead!  The best views I have had through this 20″ Obsession Dobsonian are of the planet Saturn, and the Messier 3 Globular Cluster.

It’s impossible to show you exactly what the view was like, but this photo of Messier 3 I captured gives you a rough idea. The truth is, it’s impossible to capture the beauty of the intensely dense group of stars of Messier 3 in a photo. The real-time view is much better.

M3 globular cluster

The M3 Globular Cluster

With so much aperture, the deep-sky objects that are usually dim and hard to find with an average-sized telescope are bright and detailed.  

The massive mirror in this Dob allow much more light to be reflected into the eyepiece than a typical telescope.  If you can handle all of the extra weight and transportation requirements, a giant 20″ Inch Dobsonian will offer you views of Nebulae, Galaxies and Star Clusters like you have never seen before.

36″ Dobsonian

In the summer of 2018, I had the privilege of looking through a 36″ Dobsonian Reflector telescope, at the Cherry Springs Stat Party. The combination of a 3-foot primary mirror and the dark skies of Cherry Springs State Park made for a sensational observing session. 

The Next Best Thing

If you’re not up to the challenge of maintaining and storing a large Dob, consider a smaller variation that will likely get more use. A 20-36″ primary mirror will sure pull in more “faint fuzzies”, but it’s a not a practical solution for the average observer. If memorable views of the night sky are on your agenda, I suggest taking a good look at the Apertura AD8 Dobsonian Telescope.

An 8-inch mirror is enough to reveal some of the fainter deep sky targets, yet the telescope is manageable enough to get a lot of use. This model comes with an impressive number of accessories including 2 eyepieces (I especially like the 2″ 30mm Plossl eyepiece) and a laser collimation tool. 

Dobsonian telescope

The Apertura AD8 – Dobsonian Reflector Telescope

Once you’ve got a quality optical instrument to observe the night sky with, you may want to invest in some premium eyepieces to enhance the experience. There are some incredible options out there, but my favorite type of eyepiece is one that delivers a wide field of view, such as the Explore Scientific 14mm 100 model below.


Recommended Eyepieces at High Point Scientific