Ever since I was a kid, I was fascinated by astronomy. I grew up under dark skies in Zeeland, a delta of the river Rhine in the southwest of The Netherlands. Back in the sixties these were very isolated islands. Light pollution-wise, conditions were no doubt better than almost anywhere in Europe nowadays. I regularly lay on the roof of a shed behind our house to look at the Milky Way. I had a booklet with constellations and learned those by heart. I also read some books on astronomy; one of them was about how to make to make your own telescope. I figured I could make such telescope, but how to make a mirror was beyond my understanding. So the plan stalled. A telescope had to wait for almost 30 years. After I bought and sold several telescopes, I eventually started to build truss Dobson telescopes.

On this website I will explain the how and why of these telescopes, and I'll focus on those issues where I deviated from known designs. I will go into details of the essential parts of the telescopes, such as the optics, and the Argo Navis/ ServoCAT GO TO systems.

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I observe almost exclusively in the surroundings of a house and this during vacations. This has consequences for the type of Dobson telescopes I build. For instance, I don't need a super-light/ ultra-compact telescope. But having said that, the 12 inch telescope has been with us on vacations in various parts of Europe.

What I want from a Dobsonian telescope

1. It must be well-balanced.
   
2. Collimation must be easy. Not only the process itself, the telescope must keep its collimation, whether being pointed towards zenith or to the horizon. This is often not the case. Also, the telescope should keep its collimation throughout the night. This is not automatic either, particularly with a fast optical system
   
3. The telescope must be very stable. Nothing bothers me as much as a shaking image.
   
4. Smooth operations. Not so smooth though that you have a 'runaway' telescope
   
5. It must be easy and quick to set up and to break down.
   
6. It must have a high pointing accuracy for the Argo Navis digital setting circles (see for a detailed explanation later).

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