It is currently Wed Feb 19, 2020 12:32 pm


Post new topic Reply to topic  [ 2 posts ] 
Author Message
 Post subject: Little Dumbbell
PostPosted: Sun Nov 24, 2019 11:52 am 
Offline

Joined: Sat Jan 26, 2008 4:03 pm
Posts: 524
Location: Galloway, SW Scotland
Studied M76, the Little Dumbbell, several nights ago. It was a night of very good seeing indeed, which saw me picking out four members of Stephan’s Quintet with the big Dob.

Back to M76, I do like this nebula for its interesting bipolar structure and slightly constricted centre. At higher magnifications (200x plus), I enjoyed the sight a bright core in each lobe. And some other strandy detail. Silly me, I didn’t think to look with my OIII filter. That’s on the list for the next opportunity.

There’s a very nice star field in the background, too.

I remember that I found this nebula tricky to find the first time, but now I find it easy, a matter of picking out two prominent stars, 51 Andromedae and Phi Persei. The nebula is near Phi Persei.


Top
 Profile Send private message  
 
 Post subject: Re: Little Dumbbell
PostPosted: Thu Nov 28, 2019 8:38 am 
Offline

Joined: Sat Jan 26, 2008 4:03 pm
Posts: 524
Location: Galloway, SW Scotland
Performed another study of the nebula during my session last night, this time experimenting with LPR, UHC, OIII and HBeta filters.

Seeing wasn’t quite so good, last night. Although it was clear, a slight residue mist kept coming and going, the legacy of several drizzly days.

However, the view of the nebula was still decent. Once again, the filter-unaided view showed the constricted centre and the two lobes and their bright cores. The view was slightly dimmer than last time, though, with less strandy interior detail, and I had to limit the magnification to 205x.

As expected, the LPR filter had very little effect on the presented view. The UHC gave a modest improvement, what I would describe as a small `general’ improvement in detail, without there being any structural change.

The OIII filter was a definite step up, showing an improvement in detail, and most notably in shape, which was now more clearly defined. What was interesting was that the filter seemed to reveal some strand, nebulous detail beyond the sides of the lobes.

The HBeta was a surprise. Its downside was that it had a considerable darkening effect, quite a bit more than the OIII, so I had to lower the magnification to 165x, but the detail beyond the sides of the lobes was increased, altering the hourglass figuration into something more bulbous.

I find it interesting, playing with filters. The HBeta filter was very effective on the nebulosity in the Pleiades, as well, something I’d never tried before.

Happy observing, Nigel


Top
 Profile Send private message  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

All times are UTC


Who is online

Users browsing this forum: No registered users and 5 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group