NGC1850 Ha

[lazjen]

This was another target I did on my recent dark site visit. This is 4 x 15min exposures.

I also did RGB (5 min exposures) but my processing of that data gave some underwhelming results so I haven't tried combining it with this Ha at all.

172634

Astrobin with full version(s) and details: http://astrob.in/133446/B/

I couldn't find much on astrobin to compare. Has anyone done this area in RGB that I could see what I should be getting? And if so, what exposures were you using?

[Placidus]

Ooh! That goes on the to-do list! Don't worry about what it looks like in colour - add some OIII :) Your shot is already showing the nebulosity better than the Wikipedia shot. (The Wikipedia article is a tiny bit interesting).

I think you've got globular cluster NGC 1855 and emission around NGC 1854 in there too.

[lazjen]

Thanks for the info, Mike. I'll have to see if it's visible from the backyard.... Interesting, just checked Stellarium. I might have a chance in the next couple of months as it gets a bit higher and more "westerly". I'll grab some OIII (should I try SII as well?) if there's ever a clear night.

According to the annotations on astrobin, I've NGC 1856, NGC 1860 and the tip of NGC 1847 in there as well.

If I get more data, I should try to remember to rotate the image up the "right" way. :)

[RickS]

Nice work, Chris. I don't think I've ever imaged this area. It's hard to tell whether SII is worth doing or not. You need to suck it and see unless it's a common object and there are good examples of Hubble palette images around already.

Cheers,
Rick.

[Placidus]

Whoops, that'll larn me to check which is north before sticking my neck out.

With more nuchal safety, most regions of the LMC are extremely rewarding in H-alpha/OIII, because there's plenty of both and they are often well separated topgraphically, but I agree with Rick that SII is much more difficult.

[lazjen]

Sorry for the orientation confusion - I generally don't bother changing any of my images so I forgot about it.

Anyway, I'll concentrate on the OIII first then if possible grab some SII and see what it's like. I think I'll have to attempt 15 min subs to start with - that area is a heavy air traffic region for me. Or maybe I'll live dangerously and risk 30 min ones. :)

[RickS]

I have found the d2line function in PixelMath can be used to effectively remove satellite and plane tracks from individual subs prior to integration :thumbsup:

[lazjen]

Seriously? Wow, well I have some data that I took recently that I will have to try that out on. I thought it was going to be lost as I only got 1 x 20 min sub for each RGB and I think the blue has a plane going through it.

[Rex]

Nice shot Chris. Can't wait to see the finished version.

[lazjen]

Thanks Rex - yeah, I'm looking forward to getting more data for this and seeing where it all goes.

[Ross G]

A great looking capture Chris.

Good luck with it.

Ross.

[RickS]

In my case I had a few subs but couldn't get rid of the satellite trails with rejection algorithms or a median combine. I used d2line to set all the offending pixels to a value that was easily rejected. It's not going to be quite so helpful if you only have a single sub but I suppose you could calculate your average background and set all the pixels in the trail to that value.