Old 20-10-2007, 09:51 AM
Its only a column of dust

你B is offline
Join Date: Aug 2007
Location: New Iceland
Posts: 761
early morning obs report

set the alarm for 1:30 last night for an early morning session today. Geez, getting out of bed after 3.5 hours of sleep is not cool!

Date: Saturday Oct 20
Instrument: 10" Newtonian
Seeing: 3/10 (predictably)
Transparency: 3/5 (horizon haze/fog)

Removed the covers from the scope and fiddled with the collimation a bit. Just twiddled with the secondary a bit as before Ive noticed that it may have been a bit too far toward the primary. Then I took it outside to cool. Had some coffee and biscuits then got down to business. Dew was already settling. Unplugged the fan after 30 mins and started with M42. Showed abundant detail at 104x with the Narrowband filter. In the trapezium, 6 components were resolved. I increased power to 227x, but the stars were a vibrating mess. Seeing again. They also had a flare to one side. I defocused the stars and put my hand at the top of the tube and the shadow was on the same side as the flaring. Must be tube currents. Temp was falling and the scope came from a relatively warm house. Detail in the nebula was quite apparent at 227x. I also took a peek at Rigel. At 227x, the star was a huge blurry mess, unfocusable. Very disturbing to look at. Geez! One day I will get lucky and score a truly great night! One day...

I also attempted to find the Flame Nebula. At 104x, I could just make out some nebulosity but was very faint.

Next I took a quick peek at the Tarantula nebula. The field was great at 39x, without the filter the tarantula showed detail with averted imagination plus many other goodies occupied the same field. I tried 454x on the nebula, the sky was pleasantly black and the nebula sensational, but the stars were mushy courtesy of the less than ideal seeing. You could even see the nebula rippling if you looked hard enough.

Carina was rising so I thought I'd check out Eta Carina. At 333x, without filter, I could see the loops of the Homunculus Nebula, which were an awesome bright orange colour. I tried 416x but the view deteriorated. Have to wait for better night to examine this thing. Nontheless, the 333x view clearly showed its tiny structure. I could even hint at variations in brightness in the nebula itself, despite its tiny size. This would be a pretty neat sight at 600-700x under good seeing. All I need is a 4mm radian, a premium barlow and some good seeing for once

Next up was the planetary nebula NGC 2438 in Puppis. This object is located amongst the stars of M46. At 39x, it was visible as a tiny round glow. A mag of 166x bought out its ring shape structure. At 416x with the Narrowband, it showed up quite well. It's ring structure was obvious and the East/west sides appeared slightly brighter than the north/south sides. I could detect a star within the nebula which I thought might've been the central star but turns out that's actually mag 17.5 thus invisible, so the star was simply in the foreground.

I also attempted to hunt down another planetary, NGC 2440. Then, at 4:15am morning twilight had already begun and had to call it quits. Nuts, that completely surprised me!

I checked the collimation in the lighter conditions and was surprised that it was a bit off! Well, in the 2am darkness, one's tweaking skills and visual interpretations are not the sharpest! By now, the scope has been outside for 3 hours, and the dew was vey heavy. Water was actually running down the tube. The mirrors didn't have a hint of dew, that dewshield is a godsend
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Old 20-10-2007, 10:15 PM
Lord Lissie

DougAdams is offline
Join Date: Dec 2004
Posts: 233
Good stuff. That's an amazing sketch - 416x and hand tracking!

Eta Carina is great - that's one thing my dob did show off well last year. The Homunculus was amazing - like two orange balloons stuck together.

Just Luna for me last night and tonight. I may get up early and have a look at 8" of Mars before the Rugby
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Old 21-10-2007, 12:54 PM
Its only a column of dust

你B is offline
Join Date: Aug 2007
Location: New Iceland
Posts: 761
turns out my secondary was slightly miscollimated after all! So I wasnt getting top images as I found out last night. Then I re-adjusted the secondary and was impressed

This is from last night (20 Oct)

47 TUC, in that poor seeing, was great at 454x, infact more pleasing than at 227x. Stars were tiny pinpoints and the hazy core was nice and granular, overlayed with tiny points. It appeared slightly crisper than before my secondary adjustment. Geez, what awaits me in good seeing and moonless sky?

Tarantula Neb Nebulosity showed quite well in the moonlight, but was too low (~30) therefore suffered from poor seeing.

NGC 362, showed resolution at 227x, was slightly better at 454x with the outer parts resolved although the poor seeing and moonlight made resolution of the inner half a fruitless affair, but there was still a granular form. Being small, it suffers much more from poor seeing than 47 Tuc. This will be a nice little cluster in good conditions.

I want to check out the Homunculus sometime this week, hopefully some good seeing will happen and being such an intense and microscopic in size, moonlight might not be too much of a problem. That thing is really bright and very orange. Me thinks it'll take extreme magnification quite well. God willing, one day I'll have a pair of TV radians and a powermate....
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