Expert: Paul Wagner - 11/27/2004

Question
Is there such a thing as a GOTO dobsonian, with drives that can track and maintain alignment for photography? I have not quite started to recapture my old hobby, and am still collecting data on the scope I should get. I can afford a good scope, but not with the mount required to take a big load. I've shopped a lot, and have yet to see any dobs other than look-through scopes with their manual altaz mounts. I'm not averse to building a mount if it's not too exacting a chore. I'm fairly handy, but no engineer. Advice? Thanks.

Answer
Dear Tom:

You are a man after my own heart!  You want a go-to, clock drive dobsonian, and you want to build it yourself.  I have explored this in some detail, and here's what I can tell you:

1.  Dobsonians absolutely give you the most mirror for your dollar, and to my mind, the best scope for most amateurs.  

2.  Goto mounts for dobs are expensive, but they exist.  Check out Orion Telescopes...I think they sell a few scopes that do this.  And if you are both mechanically and electronically handy ( I am the first, not the second) you might even be able to do this yourself. If you know what a stepping motor is and how to install one, you are halfway there.  

3.  An equatorial platform is the way to go for the sideral tracking.  These are quite clever devices that can hold your whole dobson and alt/az mount, and then track for up to and hour and half pretty accurately.  If you do a web search for equatorial platforms you will find both units for sale and plans.  A good platform for a 10 inch scope might cost about $1000, so these are not cheap.  

San Francisco Sidewalk Astronomers also has a great website with lots of links...check it out for more info.

Hope this helps.  And write back with more questions.  I currently have a 13 inch and 17 inch dob....and have yet to go through the effort of putting them on any kind of motorized mount.  But boy, I have thought about it.

Paul Wagner