Travel Dobson 6" f/5.6


click on the images to expand them to higher resolution 
A 6-inch Dobsonian that collects frequent Traveler Miles

Imagine yourself sitting on an insulation mattress in the Atacama desert, the Horsehead Nebula centered in the eyepiece, above of you the bare universe. Be honest. Every stargazer has this dream.

Travel Dobson weights 6 kilograms (13 pounds) and fits into the backpack or onto the motorbike. For me, traveling without a telescope is like without a tooth brush, only that the latter one you can buy everywhere you are. It travels on my trips to Greece always with me, but it was also in Kenya, Bolivia, Chile or on tracking tours in the Alps and on the Olympus.

6" Aperture can mean a lot, if the sky is really dark and transparent. My best conditions in my life I had on the Altiplano in Bolivia and Chile at 3,800 m elevation (12,500 feet) where the milky way cast shadows and the Eta Carina Nebulae was full of overwhelming detail.    


reise_dobson_spiegelzelle_2.jpg (56712 Byte)

The Concept: 

It's the same 2 bar design like at the bigger brother Travel Archimedes, only that here no reinforcing strings are needed.

The mirror is the most accurate, that I ever made (see Exceltestsheet). At the star test I can't see any defects, so I would give it a 2 for "lucky b@$#@rd!" as of Bratislav's mirror rating scale. On planets it shows as much detail as an expensive 4 inch apochromat. 

No focuser is mounted at all. My favorite eyepieces are quite homofocal and so focusing can be done by sliding the eyepiece in the 1" sleeve.

To balance the scope with eyepieces of different weight I use magnets, that can be placed at the front end next to the eyepiece or at the sheet steel at the backside of the mirror box. I added this steel sheet counterweight to bring the balance point down, since compactness was a bigger design requirement than weight. A brake is activated while changing the eyepiece.

4 altitude bearings are mounted at the mirror box. When looking close to the horizon, the instrument can be tilted for a more comfortable view.

For transport, all parts like bearings, secondary - eyepiece assy., eyepieces and bolts fit into the mirror box, separated from the mirror by the mirror cover. All components are very stable and motorbike approved.

 

 

^ to top of this page               Home