Hi Everyone!
Just came across this forum after I bought my telescope a week ago. I'm just starting out again after a long absence from astronomy as a childhood hobby. I was in an op-shop when I saw an old Tasco 132T 76mm reflector in a box for $10. It had 6mm, 20mm eyepieces and a 2x Barlow, a T-piece for a camera, and a moon filter. After putting it together in the shop and testing it, checking that the mirror was good etc, I thought I couldn't go wrong for that price. The only catch was that the mount and tripod stand was missing. After googling for different types of mounts I decided that I could make my own, so I went back to the shop and bought it :-)
I had an old camera tripod, and with a few bits of brackets, I had a makeshift stand happening. A bit dodgy, but it worked. Now to search the sky hehe!! Damn, three days of total overcast skies and light rain
.
Got really sick of looking at distant trees and buildings. But finally the stars came out. My first look was at venus and jupiter. Now, I hadn't looked through a telescope for 30 years, and even then, it was just a small, cheap refractor, probably 2.5" or thereabouts. I was blown away to see 4 moons of Jupiter again, but better than I ever remember!! And to see the Great nebula in Orion was really great! I'm thoroughly enjoying this little scope!
Now that I've got around the sky a bit I want to get the mount happening. I decided to build a little tabletop Dobson mount, off some of the designs i'd seen here and on other sites for larger telescopes. Living in Tassie here, I had access to some beautiful native timbers, and so I built myself a Dobson mount out of Tasmanian Blackheart Sassafras timber, and polished and oiled it. It looks gorgeous, and is MUCH steadier and smoother than the tripod. A total improvememnt and a pleasure to use! I pivoted the round base on a piece of Tassie Oak board, with some thin nylon sheet circles between the board and the mount for smooth slip when rotating - it works a treat! The tension can be loosened or tightened with a wingnut on the pivot bolt. If anyone is interested in this design, I could take photos and 3-view drawings and upload them here. You can simply scale them up for larger scopes than mine.
Now that I've got that happening, I started thinking about making an equatorial wedge for it and mount the Dobson on it. I searched out the basic designs and working theory for an equatorial mount and I think I understand the principle. I may even put a home made tracking motor in it later!
Here is my question:- given my lattitude for where I live (Hobart, tassie) which is:
Lat: 42 50 34 S
Long: 147 17 18 E
At what angle from level should I raise a wedge surface to sit the Dobson on to be correct for an equatorial mount? How would I find this info out? Or is it not as simple as that? Are there other things I should know? I've read up on the setup procedure for an equatorial mount for the southern hemi, and I think I understand how to do it. I got a rough approximation by trial and error just by inclining my mount and facing the incline roughly south and tracking a star with my hand.
Any info would be greatly appreciated.
Cheers, Graham