RE: (IAAC) Obj: Jonkherre 900 (PK 194+2.1) - Inst: 51cm f/10 classical Cassegrain
Thanks for the comments. My own rating system is also subjective and I'm
always on the lookout for something better, er, shall we say, more
objective, without resorting to the need for a professional photometric
assessment of known markers. Others have suggested using an evaluation of
close doubles as a way to go about this. I don't know. However, I do
typically record a fair amount of environmental data as a part of my normal
observational technique, and typically include an assessment of faintest
magnitude visible, naked eye and/or telescopic. In example, here's an
excerpt from the evening of the 22/23rd of October:
M31-G205 RA 00 43 9.8 Dec +41.3594444 Type GC (globular cluster)
Comments: 46cm. 642X. 14.8 magnitude GC, appears very small and diffuse.
Dimmer than the cited magnitude. Easily located 4' southwest from an
asterism of three 12th magnitude stars. Very diffuse. Best seen in averted
vision. G199 and G200 are located in the same field of view.
981023 0520UT-O525UT, clear with intermittent thin cirrus, 40F, 6.5 visual,
16+ telescopic, Good Sky Contrast. Charlie Elliot Wildlife Management Area,
Mansfield, GA. Uranometria page 60. Sketch at 642X.
Big Dobs - "Size Does Matter"
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