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Van den Bergh 141; Ghost Nebula with DSLR


astrovirus

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So, this summer I am spending a 2-week holiday with the family in the Belgium Ardennes near the German/Luxemburg border. After having a lot of trouble with the connection of the 350Da to my field laptop (USB connection getting lost all the time, ruining 2 good imaging nights already), I managed to gather 1 night of good data on VdB 141, although conditions were far from perfect with a 70% lid moon up. This image contains 4 hours 30 min (27x 10 min) ISO 800 lights, 18 darks, 20 bias, and 30 flats and was captured with the peltier cooled Canon 350Da (TEC@10°C) on the 8" newton. Data was reduced with DSS 3.3.2 and processed by the DSLR-LLRGB method in PS CS3. I hope to resolve my USB issues to be able to image some more targets, but I'm happy with this result for now.post-6675-0-57582700-1374325254_thumb.jp

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Thanks Richard and Freddie,Sure I don't mind other poeple giving a go at my data, we all learn from it. Can you tell me what you actually did Richard. It looks a bit hard, but that's probably form processing the jpg I uploaded to the forum. I would like to try what you did on my full res image.

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Yup, Richard has just dragged the data past the noise limit in my view. (Sorry!) And on this cursed object the noise limit appears very early!! Attempting it with a DSLR is truly heroic but you have done well and I think you judged the stretch very well, quite honestly. I spent 22 hours on this from a perfect site with a sensitive CCD camera and it was still a nightmare. So well done indeed.

Olly

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That's a lovely image with lots of different features to look at. Richard's reprocess brings out some more detail but is way too over processed for my taste.

You are right Freddie, but my original didn't show this over provcessing at all, so I feel It had something to do with the uploading to to SGL - lets see if it is better through Flickr

9327464837_63ef671c6b_b.jpg

VdB141-2013-DSLR-LLRGBfinal-2000px by sologuitarist61, on Flickr

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That's a lovely image with lots of different features to look at. Richard's reprocess brings out some more detail but is way too over processed for my taste.

You are right Freddie, but my original didn't show this over processing at all, so I feel It had something to do with the uploading to to SGL - lets see if it is better through Flickr

9327464837_63ef671c6b_b.jpg

VdB141-2013-DSLR-LLRGBfinal-2000px by sologuitarist61, on Flickr

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Richard, for my taste, the background now is a little to dark, and I think the sharpening also brought out a lot of noise. Olly is right here, and that is why I left out any sharpening in my own processing as it just popped up the grainy looking noise in the dust. Thanks for the compliments Olly and Gina.

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Like the original, very subtle with a DSLR or otherwise - (Sorry Richard but all I see are sharpening artefacts right across the whole frame)

Me too. Plus some angry monochrome pixels. The truth is that this is a faint, faint object. It is really just a bit of glorified background sky and it can't be bullied, which is why I kept going for 22 hours on the darned thing! Even then I used quite heavy noise reduction in places, something I really hate doing. This has just 4.5 hours - with a DSLR - and under bright moonlight!!! I'm amazed that the signal is as good as it is. Astrovirus, if I were you I'd try for more data under a moonless sky if you can, but I guess that the trip to the Ardennes isn't something you can do just any time.

Regarding the blackness of the sky on this target, I'm convinced that it really is abnormally black in places due to the presence of thick sooty dust. Parts of the sky here do tend to look black clipped when I don't think they really are. I looked at this effect very carefully indeed when processing. I reckon that blackness is real.

Whatever, this is one of the spookiest objects in the sky. The little human figures really do get to me. It is impossible (for me) not to see them as human. I try to tell my eyes that they are just dust columns but they won't listen to reason!

http://ollypenrice.s...A 20 HRS-X3.jpg

Olly

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Thanks Francis. I will certainly add more data to this set in the future Olly, but as you already guessed, it will need to be done from a dark place, so my home backyard will probably not work. So it will either have to wait another year, or hopefully I can add data at our spring or fall starparty which is also held at a dark sky site.

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A spectacular DSLR image, congratulations! :) You've picked up a fantastic amount of dust and maintained wonderful colour. And with a 70% moon!?!

I totally agree that you can't drag the background up too much, however I do think that the image is a little darker than it could be. i.e. the stars only seem to reach about 3/4 of the available dynamic range, if that makes sense..?

But that's just nitpicking really. You've done very well to show what can be done with a DSLR in the right hands :)

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