Thank you for the kind feed back, much appreciated
I have considered gathering my obs. reports on a blog, -- I do have them much more organized in proper categories on my pc, and would like to present that on the web. Just haven't got around to that, yet...
Meanwhile, here's the report from my latest observation, of :
M51, The Whirlpool
”Mad dogs and englishmen, walk in the midday sun...”. Thus wrote Kipling somewhere, -- I forget the context, but the line came to mind this summer night, when trying to catch M51, the Whirlpool galaxy. ”Mad dogs and danes, observe in the midsummer night...”.
The star hop to M51 is easy : from the end of the Dipper’s handle (Eta UMa) -> 2° E to 24 CVn, then -> 1.5° S to a triangle of 7m stars ; M51 is just east of the S corner of this triangle. The conditions this early morning (00:30 Local DST) are however rather bad: though the transparency and seeing are just above medium, the cocktail of a Bortle red suburban backyard, nautical summer twilight, plus a 73% moon at 18° altitude in the SE, all this combines to the effect that I can’t even (as possible in autumn and winter) spot the galaxy with my 10x56 bino.
Now switching to the Vixen FL-80S/640 refractor, and using my ATC K40mm finder eyepiece, for 24x @ 1.7° FOV, i can just glimpse a faint nebulous area at the proper location of M51, -- but even this requires an effort plus averted vision. No chance of producing a drawing of any value under these circumstances!
And then again...
Switching to my R2 eyepiece, I immediately see two bright hazy stellar cores, each surrounded by nebulosity. Adjusting the integration and gain, structure starts to emerge in the nebulae (106x @ 0.3° FOV). I sit down and start to make a drawing: the face-on galaxy NGC 5194 (aka. M51a) displays 2 obvious, grand spiral arms, while the dwarf galaxy NGC5195 (M51b) shows a couple of clearly brighter lines (like eyelids) around the lenticular core. The arms of M51a show angular bends plus hints of ”knotty structure” (starburst regions), both the result of close gravitational interaction with M51b.
Comparing my drawing to that of Stephen J. O’Meara in his book ”The Messier Objects”, I can see much more detail in M51 (with the exception of the bridge between M51 a-b) with my 3” refractor and R2 Eyepiece from a NELM 5m sky, than he was able to with his 4” TV Pronto refractor from a pristine NELM 8m sky (3.600 ft up, at Volcano, Hawaii), ”where the Milky Way is bright enough to cast shadows...”
Some are questioning, whether this kind of observation can be called ”visual”, arguing that only photons collected by glass should fit this definition. I totally disagree with this attitude. In my view, any personal registration and description of an object (be that textual or graphic) done by viewing it ”real time” at the telescope under the night sky is ”visual astronomy”. I don’t care what image itensifiers are used, -- more aperture, a ccd+lcd or a NV eyepiece... If I can get a view of M51 in my small 3” refractor matching that of a bulky 18” Dob, I will go with that, especially when the observing conditions are otherwise impossible.
(PS: will post a link to the full obs. report here, soon)
Edited by AllanDystrup, 26 July 2016 - 09:53 AM.