Like what you saw in the images, the sky condition was far less than ideal. Though the high-level haze reduced in the second half of the night, I would rate the overall sky transparency at 6~7 out of 10. Seeing was also mediocre, 7/10 at best.
Despite the mediocere sky condition, we managed to see tons of stuff with Richard's 15 inch monster Dob. Below is a brief report on the highlights of the night. Well, not so brief, so I'll break down by catagories and write slowly...
Nebulae:
California Nebula (NGC1499): Well this is the biggest surprise of the night for me. I've attempted to see this neb with unaided eye and binos for numerous time before, under much better sky conditions. Absolutely NO success. However in this memorable night, with the help of H-beta filter, the nebula was VERY easy in the monster Dob while the crescent moon hadn't even set!
The nebula could be traced to its full extend, beyond 2 FOVs with the 40mm XW eyepiece. No fine structures could be seen though, due to the poor sky condition.
Horsehead Nebula (B33 against IC434): The H-beta filter really does magic. The Horsehead could again be seen easily with direct vision! Averted vision revealed the shape nicely. The background neabula IC434 (the red-colour triangular shape nebula we see in images) could be traced to as long as 1 degree running north-south. Look forward to better sky condition next month so that we can push to a higher magnification for a close-up look on the horsehead!
Orion Nebula (M42): The view as not as good as two weeks ago thanks to the haze and clouds. However the fine feather-like structures in the two wings, as well as the dark nebulae between M42 and 43 were very impressive to someone like me who doesn't own a big Dob! The greenish tone, not surprisingly, wasn't seen so well. Guess we can keep the pinkish-tone challenge for next session.
Monkey Head Nebula (NGC2174): Kochu imaged this intersting nebula shortly before, refer to his post here:
viewtopic.php?f=7&t=10562
Last time I saw this object was some 10 years ago with my 8-cm refractor under very dark sky. Tried a few times under Punggai/Mersing skies later with no success. Well aperture rules here, it was very easy in the 15 incher aided by OIII filter. The dark nebulae which was the monkey's eye, could be seen easily as well. The overall monkey head-shape could hardly be imagined though XD...
Eskimo Nebula (NGC2359): The best Eskimo I've seen so far. The inner shell could be seen distintly, with quite a bit of mottled/netted look. Outer shell finally appeared uneven. Can't wait to have a even closer look under better seeing conditions.
Rosette Nebula (NGC2237): Another memorable one for me. Though the nebula was way too big to be fit in the FOV entirely, the central dark hole, and numerous bright/dark structures surrouding the hole could be seen easily. If only the FOV of the scope could be larger!
Thor's Helmet (NGC2359): I wasn't aware of this fine object before. I somehow didn't include it in my ETX-125 GOTO deepsky marathon back in 2006 when planning. The object is far better than many others in Canis Major; given the mag-7~8 sky that night, what a waste...
Through the 15 incher in OIII, the 'horny' helmet feature was easy and impressive. The third and fourth horns extending north-ward could also been seen, but not too obvious limited by sky condition. This one is definitely a must-see if one has a monster dob and OIII filter.
Ghost of Jupiter (NGC3242): The view once again impressed everybody. Like Yang Beng described, the mottled inner ring and the central star could be scrutinized closely in magnification as high as 700x! The bluish tone adds to its beauty.
This object is bright and stands to magnifications very well. A fine target for urban observations if aided by filters. During my NTU astro club days, people were in general quite impressed when we showed it to them.
Eight-Burst Nebula (NGC3132): There's a very famous image of this fine planetary by Hublle telescope (
http://en.wikipedia.org/wiki/File:NGC_3132.jpg), showing it as something resembles closely to a gem stone. The southernly lacation prevented observers in the north to see this wonder.
visually through the 15 incher, it was big and bright, showing almost the same structures as in the HST image. Another intersting feature of it is that the bright star shrouded in the nebulosity is not the real central star, but a foreground one. The real central star was much dimmer and close to the bright forground star. Elton and Richard successfuly saw it in high power, but I somehow couldn't get it. Guess I can conclude after years of visual observations that my eyes are more sensitive to faint nebulosities than to resolution-demanding features like planetary details and double stars.
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We also tried a few really challenging diffuse and planetary nebulae like NGC2264 (Cone Nebula), Abell 21 (Medusa Nebula), PK238 34.1 and NGC2610. All could be seen with the help of filters, but featureless at best. Like Yang Beng brought up, the sky condtion was just not there.
Clear skies please...