Posted 29 January 2012 - 02:50 PM
Posted 29 January 2012 - 07:43 PM
Max I have to say that with that pier and a 1250mm f/l scope near the horizon I am standing my 6'4" on the step next to the pier, and when looking at the zenith 'straight through' I am sitting on the step with the eyepiece just a few inches from the pier and quite low really. but the mount is really super steady on that 1/2" thick 6" diameter cardboard pier - that weighs in at about 20lbs.
From my home position I can't observe anything near horizontal, and due to atmospheric conditions, don't do anything serious below thirty. Using that info as a starting position, actually diminishes the up/down eye movement considerably. I like to sit when I observe, preferably almost recline, so a comfortable astonomers stool with notched risers in fairly small increments, within safety limits should suit me fine. I hear what you're saying about closeness to pier, and will either make a simple alt/az balanced mount with large altitude projection, or just simply not observe at zenith. On that note, re your other post, although I'm going to give it a go in not using a diagonal, I have to say that I've never seen a hybrid .965/ 1 1/4" PRISM diagonal; where did you get it?
Posted 30 January 2012 - 04:43 AM
Posted 30 January 2012 - 08:57 AM
Posted 30 January 2012 - 10:36 AM
Recently I acquired a 70mm f/12.9 achromat. I might try the experiment again using all the 1.25" diagonals. Maybe a prism diagonal will improve the slight CA in this scope?
Posted 30 January 2012 - 11:01 AM
That's a very interesting experiment you did there. I for one would be very interested to hear the result, if you do something similar with the new scope. It's not often that anybody has such a comprehensive set of diagonals to do such a test.
Posted 30 January 2012 - 04:33 PM
the other looks like it might have the same, but I couldnt unscrew it.
Posted 30 January 2012 - 04:47 PM
'Meade Hybrid Erecting Prism #931' with a 45 degree prism
so obviously they were made - both are on clearance at telescope house in the uk for £37
Posted 30 January 2012 - 06:05 PM
Many thanks for taking the pics, and doing the research! The numbers are particularly useful.