by David Staples
Last night was one of those rare nights of great seeing...at least in Santa Rosa. Which is good since I just recently picked up a new William Optics 2 inch diagonal and needed to collimate my scope (C8) to match the diagonal. When I first put the diagonal in last week, HOO BOY, every star was a new comet.
What a difference between diagonals. My old one is a generic 1.25 Chinese mirror diagonal. I thought maybe I had banged the scope around somehow and messed up collimation. I put the old diagonal back in and collimation was back where it should be. Certainly says something about the mechanical quality of cheap Chinese stuff. Well last night provided the opportunity to collimate with the new diagonal in place ( which by the way seems to be orders of magnitude better in build quality) and see what difference it would make.
Seeing last night was good enough to see second diffraction rings in focus at 541x so I think I pretty much tweaked the scope back to where it should be. Epsilon Lyrae was split at 169x with dark space and diffraction rings around all the components, I don't I think was ever able to say that with the old diagonal and similar conditions. At 338x you could drive a truck between them.
I also took a look at Antares to see if I could split it. I think I did (at 338x), but it could be averted imagination. Starting at north and rotating CCW, I would put the position angle at about 270 to 275 deg. Is that anywhere near where the companion should be? M13 and M22 were stunning at 400x with arcs of stars in M13 making it seem like the bones of a galaxy.