Over the last several weeks the 20-inch has been out of commission as I cleaned it up and prepared to install a new mirror. Weather has not been very good with poor transparency and seeing. I wasn't motivated to complete the work until I saw the forecast for next week which is to be clear with at least good seeing. I cleaned the ground board and the electrical contacts, dusted the whole structure, and installed a new focuser. I took great care to align the secondary and focuser properly. In went the mirror and I tested focus one night, finding I needed to keep the poles a little long (they needed to be cut a few inches in any case as I was going from f/5.25 to f/5, and using a lower profile focuser. Last night I cut the poles and installed all the accessories. I still needed a fair amount of counterweight as the new mirror is around 15 pounds lighter than the old one. All the eyepieces focus, although I did notice some astigmatism which I will need to track down (probably with the cell and sling). And to my delight the cleaned ground board carries the electric current very well now, so I had no issues with the motors cutting out. Tracking was great and pointing settled in after a few synchs.
Also, instead of continuing on with SkyTools 4, I reverted back to SkyTools 3. It was clear the developer was not going to work out a solution to the column sorting problem, so I decided to ditch ST4. ST3 is running very well, I have all my old lists back and there is no f-ing algorithm telling me what I can or cannot observe. Back to normal.
All the assembly and care left me a bit tired, but I did try a few objects, including a faint Cocteau pair which I don't think I would have tried with the old Swayze mirror. The Z has bright new coatings and showed no pinholes with a light to the back of it. Star test seemed a bit better along the edge, though the Swayze was no slouch. M13 looked really nice.
STF2161 AB: 508; 140x: Bright white stars, 1 Dm, fairly closely split around 4". WDS says it's physical, but there is no -41% overlap of the parallax ranges, it is not binary.
17h 23m 40.97s +37° 08' 45.3" P.A. 321.00 sep 4.1 mag 4.50,5.40 Sp B9.5III dist. 120.63 pc (393.5 l.y.)
COU 626 AB: 508; 285x: A is white and easy to see, B is very much fainter and needed averted vision and foveal coaxing, but I was able to see direct, closely split around 4". WDS uncertain, but there is 47% parallax range overlap, 1,352 AU weighted separation, 1.5+0.9 Msol, and the radial velocity delta is the same as the escape velocity 1.8 -- so chances are good it is binary.
17h 22m 12.17s +32° 48' 10.3" P.A. 272.00 sep 4.2 mag 10.77,13.00
ES 2227 AB: 508; 140x: Easy near equal pair, well split, white. WDS says parallax indicates physical, and there is 7% overlap of the parallax ranges, 1,752 AU weighted separation, 1.4+1.4 Msol, and the radial velocity delta 0.1 is less than the escape velocity 1.7, so it is very likely binary.
17h 22m 15.42s +36° 09' 25.5" P.A. 177.00 sep 4.8 mag 11.26,11.46
ROE 108 AB: 508; 140x: Very slightly unequal, well split, white. WDS says parallax indicates physical, and there is 51% parallax range overlap, 2,224 AU weighted separation, 1.5+1.5 Msol, and the radial velocity delta is 0 with escape velocity 1.6, so it is likely binary.
17h 22m 11.84s +30° 09' 36.7" P.A. 1.00 sep 6.0 mag 10.98,10.99
STF2162 AB: 508; 140x: Very pretty near equal white stars, closely separated around 1". WDS uncertain, and there is -16% overlap of the parallax ranges, 356 AU weighted separation, 1.8+1.7 Msol, and the radial velocity delta is 0 with escape velocity 4.2 -- it might be possible to be binary but the Gaia data should be pretty accurate, this is likely not binary.
17h 23m 54.55s +36° 27' 28.0" P.A. 285.00 sep 1.3 mag 9.39,9.57 Sp A2 dist. 369 pc (1203.68 l.y.)
COU1142 AB: 508; 285x: Light yellow bright A, B is very faint and appears as a point just beyond A's diffraction, seen with direct vision but it's tough. There's an Aa-Ab pair, HSL 1, which is binary. WDS says COU1142 is physical, but there is -26% overlap of the parallax ranges, and in spite of the small 99 AU weighted average separation and 1.1+0.5 Msol, it is likely not binary.
17h 24m 42.41s +38° 02' 10.5" P.A. 222.00 sep 1.8 mag 8.18,12.21 Sp G5 dist. 50.61 pc (165.09 l.y.)
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