At long last. The clouds cleared for once so now I could get a good long session for the first time with the 10" dob.
Well I set up well after dark. Plugged in the fan and waited 45 minutes. Then to my horror, there's cirrus covering half the sky. Melbourne's weather has done it AGAIN!
After I was satisfied that the scope was cooled, I checked the collimation and it actually stayed put since the previous session. So no need to tweak it!
Date: 9/10/07 evening - 10/10/07 morning
Telescope: 10" Newt
Seeing: 5/10
Transparency: 1/5 with intermittent cirrus, later cleared to 3/5
Started with
Uranus. At 227x it was a tiny greenish orb. I increased the mag to 333x in an attempt to spy a moon or two but the seeing was poor and just blurred the planet.
Now that a lot of the sky was covered in Cirrus I turned to
47 Tuc. At 454x you could actually see it undulating, like water in a slight breeze. Nevertheless, it still looked magnificent, dark rifts and star chains gave way to mist overlapped with tiny pinpricks of light as you moved in towards the core.
I then waited for the cirrus to clear. I had a look at
NGC 253, but it was little more than a large, elongated blur from this light polluted location.
My next stop was the
Tarantula Nebula (NGC 2070). Using the Narrowband filter at 39x was awesome - the big bright blob of the Tarantula was surrounded by a myriad of tiny little knots and areas of haze. I decided to "core punch" the Tarantula, putting in my highest magnification of 454x (with a cheesy, no name barlow which isn't even multicoated!). It looked great, with numerous filaments and other fainter areas of nebulosity. The main area consisted of two circular filaments opposite each other, which to me looked like the fangs and abdomen of the spider joined at the thorax. A long, claw-like structure shoots away from the complex towards the east. I tried using the narrowband but at this magnification, no improvement was visible. I also experimented with lower powers and the filter. At filtered view at 208x was INSANE! The central core was surrounded in miles of nebulosity, you know, that stuff you've seen in long-expose photographs! At least half the FOV was covered, f not more. Amazing!
Then I did a filtered sweep of the area at 69x which was wonderful. Little knots and hazy things everywhere! And they were bright.
Wish I had dark skies!
Next I observed the galaxy
NGC 1316 (Fornax A). At 166x both it and its companion NGC 1317 were bright. The larger member showed its elongated form well.
The
Fornax galaxy cluster was just up the road and I was curious to see this. The cluster is fairly spread out so I used 69x to fit the galaxies into the FOV. I could fit 6 galaxies into the same FOV. They showed up well despite the light pollution except for NGC 1382. I could hint at some elongation on NGC 1389.
The next target was
NGC 1360, a planetary nebula, also in Fornax. Scanning the area at 69x, I couldn't see it. At 104x I still couldn't see it. I inserted the narrowband and there it was! A large faint oval oriented NE/SW. The NE half seemed brighter than the southern half and the brightness appeared to just taper off whereas the NE side had a more defined edge.
Orion was well above the horizon by now so I finally got a look at M42. I was not dissapointed. A filtered view at 104x was amazing, the thing was really bright, presented a greenish hue and you could actually see mottling and ruffing in that central bright area. The "wings" of the nebula extended beyond the FOV, I could trace nebulosity at its western edge right down to star V372. WIthout the filter, at 104x I could easily see the E and F components of the trapezium with direct vision. Very easy. At 454x, the nebula was massive, detailed and bright, but the stars were jiggling about and were flaring, betraying poor seeing. So the 104x view was the most pleasing overall.
By now, it was 2am, and water was dripping (not kidding!) off the dewshield. Both finders were fogged up. So I packed it up. Upon bringing the scope inside, even though the tube and dewshield were literally soaked, with water running down them, I was pleased to discover that both mirrors were still pristine!
After the views I got at the highest powers I have, I've decided I need higher magnifications, so must get a good barlow lens and a 4mm TV radian...I think in good seeing I could get 500 maybe even 600-700x out of this scope with these quality accessories on many objects with good results!