I think I mentioned that the bottom end of the scope was too low to reach the zenith. Since I had to struggle mightily to get this piece of 6" OD tube bored to fit the CI-700 mount head into it, I was not happy about the prospect of doing this again. But it turned out that I had a 12" Losmandy extension sitting around that fit in the middle just fine.
Click to enlarge
Okay, I was 2" too low before; now I'm 10" higher than I need to be. At least it clears the ground board!
A couple of additional annoyances:
1. Before, I was only occasionally in awkward positions. Now, I am a little reluctant to stand on the stepstool required to get into some positions (such as the Ring Nebula this evening). This is a downside of an equatorially mounted Newtonian reflector this massively large. (And not the only downside.) The only real alternative is a rotating tube, either in full, or at the eyepiece end. This may be more work than it is worth.
2. We are coming up on the summer solstice in a few nights--and we are so far north that you still don't have much in the way of stars out until 10:30 PM.
3. There is still some sort of problem with not having quite enough movement in the mirror cell to get perfectly collimated. It's not bad, but it's not perfect, either.
4. Something is still flexing a bit as I move the scope across the sky. I wondered if the diagonal spider (the part in the upper assembly that holds the diagonal mirror in place) was too flexible, and this was causing my problems. So I machined an adapter that let me put my laser collimator tool into the diagonal assembly, and then watch the laser beam's position on the main mirror as I moved the scope around. Dead solid--no motion. So perhaps the problem is flex in the main mirror cell.
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