Morning Gerhard Had a look at your 300mm image and not much one could do with that--so you need a better mount.Its easy enough to construct an altazimuth mount using standard pipe fittings. In my early days of tracking I made such a mount and it worked quite well. Maybe today one doesnt use mild steel pipe fittings and its all plastic but one should be able to get the necessary mild steel fittings . What you need is a mild steel pipe about 5-6 feet long, around diamater 2.5 to 3 inches and put the one end in concrete making sure the pipe is truly vertical using a spirit level. Before putting the pipe in the ground have the one end threaded so that it can take a matching "T piece". Also mount a plastic 360 degree plastic protractor just where the thread ends - one could get two sizes - one about 3-4 inch diamater and the other about 6 inches and graduated in 1/2 degree intervals from the CNA ( Central News Agency). This will form your azimuth bearing. Then get a short threaded ( about 2 inches or so) length of pipe - I think they are called "nipples" in the industry - one end screws into the one part of the T piece and on the other end you mount a pipe flange. This will form your "altitude" axis. At the same timet mount another 360 degree protractor on this end of the T piece and this will form your altitude circle. Your "bearings" are actually the threaded bits of pipe- not ideal as normally these threads ( about 8 per inch) have a slight taper on them - ideally if you know someone locally with a lathe you could ask them to cut the threads. You can mount your camera/whatever on the pipe flange and then you should have a nice steady cheap mount that you can aim in azimuth and altitude. If my instructions arnt that clear I could make a drawing and send that to you. I suggest you work in azimuth and altitude. Working in RA/Dec with your set-up is more difficult and unless you have a sort of permanent mount setup you would have to setup every time you observe. Whilst we report our positions in RA/Dec I think most observers work in az/el if using a mount of any sort (unless they have a permanently mounted equatorial mount)- certainly az/el is more convenient for slow moving stuff and especially geostationaries . Binocular observers will probably prefer RA/Dec but this requires preparing for observing with little charts etc so as to find the location or working in "real time" with star charts etc. In tracking satellites one wants to be able to easily jump from one position to the next - dont ask me how Russell and David for example observe so many satellites in such a short time - used to take me many minutes to find a star field and even longer to get a position! Scott has/had a nice picture on his website of one of his earlier setups where he had a homemade mounting for his video camera - made out of wood - sort of dobsonian type mount - this would be ideal for your situation as it would be easy to add "setting circles" etc . I could probably find the picture of it somewhere in my thousands of files if no longer on Scotts webpage. Hope this helps Cheers Greg ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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