The Modern Dobsonian

Would you like to learn the fine points of building everything from light-weight giant Dobsonians to tiny travel scopes, and to help keep you from making expensive mistakes? Look no farther. TMD has been constantly updated so  your next project will be a success - and not an old-fashioned heavy dinosaur! Order your copy today!

This 16" is one of five built in 2010. They weigh 68 pounds and fold up to fit into a small storage bay of our motorhome. Now that is a travel scope!

Travel Scopes

Tom Clark pioneered these fold-up designs where all the parts nest inside of each other for easy transportation and storage. The mounts are rock solid, while being easy and fast to assemble.

This 18" f/5 was built for a trip to the southern hemisphere in 1994. Total weight is 97 pounds. We observed with it from Lake Titacaca in Bolivia, at an altitude of 12,800 feet. What views!

Nesting Design for Portability

Large Telescopes

Tom built The Yard Scope in 1992 and it was one of the largest amateur instruments in the world at that time. The 36" f/5 mirror is one yard in aperture - thus the name. The 540 pound monster is one of the most famous amateur telescopes ever built. The 360 pound 36" f4.5 Yard Scope II was built in 1998 and used at the author's home in Chiefland, FL until replaced with a 42" in 2003.

Order your copy of The Modern Dobsonian today, and learn from the author's 25 years of experience in building telescopes.

Tom Clark

13720 Butterfield Trail NW

Deming, NM  88030

Medium Size Telescopes

The most popular amateur scopes are the 12-20" sizes. Under the name Tectron Telescopes, Tom Clark has built nearly 200 telescopes for customers around the world. On the left is an early 25" f/5 that weighed 250 pounds. Below is the 24" f/4.5 that replaced it when we started building ultra-lights. This 24" f4.5 only weighs 160 pounds, yet is ultra-stable. It folds up into a 30x30x24" box for traveling. Two of the 24s could easily fit into a minivan.

Here is the author with a 32"

f/4.5. It features a removable mirror box to make set up very easy. This scope could be set up with two guys in less than 10 minutes. Any scope that is easy to transport and set up is one that will be used a lot.

Above is Tom's 24' home-made dome that is on the edge of the club observing field in Chiefland, FL. The scope is a 42" f/4. It is 14' long, weighs 1600 pounds, and has a go-to drive to make observing from inside the dome a pleasure.  This telescope was moved to the fabulous skies of New Mexico in 2012.

This 10" f/5.6 weighs 56 pounds and isn't a lot bigger than the 8", yet provides excellent views. TMD shows the construction of my 18x18x20" 12" f/6 that only weighs 54 pounds. Can you imagine an 8" f/6 that only weighs 25 pounds and folds up into a 12x12x13" box? Here are the photos.

Tom's workshop in 1992 with six 15" f/5s under construction. Tom retired from telescope production in 1999 and no longer takes orders for telescopes. He still builds scopes and observatories for his own enjoyment.

First published in 1992   

Now in the Fifth Edition - revised in 2010 

8.5" x 11"  92 pages

$20 shipping to your US address.

The Yard Scope 36" f/5

The Yard Scope II  36" f/4.5

24" f4.5

8" f/6

6" f/8

Above and below are Tom's personal scopes. The 8" and 12" fold up so small that they can be carried anywhere. The 24" is used in our yard in New Mexico, and taken to star parties around the country. Compare the size of the non-folding 6" f/8 with the folded up 8" f/6, 12" f/6, and 24" f/4.5.  The cart the scope is sitting  on allows the author to easily load  the scope into his van by himself for trips to star parties.

12" f/6

24" f4.5 at the Winter Star Party

16" f/4.5 and 24" f4.5 set up at 8400' in Colorado

Learn to design and build your large Dobsonian so that it will be extremely light for it's size, provide the best images possible, balance without counterweights, and fold up into the smallest package possible for transportation and storage. No one else offers these features…

Old fashion telescopes take a lot of room for storage between observing sessions.  Here in one small corner of the author's garage , sitting on mobile carts, (from L-R) are a  12" f/6, a 10" f/6. an 8" f/6, and a 24" f/4.5. Sitting on top of the 24" is the eyepiece box used for traveling. So how much room does your current scope take up?

The author's 160 pound 24" f4.5 is shown folded up in the photo above, and on the left is a photo of it assembled. The scope folds up to 24" high, and 31" square. It will fit in nearly any hatchback. Several of them could fit into our mini-van. Set up only takes a few minutes, and the views through it are absolutely stunning.

Sold out and out of print. Thanks for 23 years of printing.