One of our Society (John G - please visit his blog: see link) bought a 2" UHC filter that he lent me, so being knowledgeable of the sky, and it being winter, I decided to try it out on a rather strange patch of nebulosity near Sirius called 'Thor's Helmet'. After screwing the filter in place on my Camera adaptor and refocusing, I did a range of exposures from 30 seconds to 3 minutes, all of the longer ones trailing, and some of the 30 second ones trailing also. I detrailed all the trailed ones using the filter manually in Paint Shop Pro 7 just as jpegs, and ran them through Deep Sky Stacker. I was struck with the beauty of the resulting picture that appeared in front of me. And when I processed them in PSP7 I was stunned with the result. DSS selected 18 exposures, most 30 seconds, 3 of about 70" and 2 about 3', but equivalent to ~30" because of the detrailing process, of which it took an adaptive weighted average. Thor's Helmet, NGC 2359, is 7ยบ from Sirius and exists because of a frantic massive star, called a Wolf-Rayet star near its centre. There is Oxygen O III (or O2+) emission in the centre and Hydrogen clouds further out.
Thursday, 29 January 2009
A stellar tantrum
One of our Society (John G - please visit his blog: see link) bought a 2" UHC filter that he lent me, so being knowledgeable of the sky, and it being winter, I decided to try it out on a rather strange patch of nebulosity near Sirius called 'Thor's Helmet'. After screwing the filter in place on my Camera adaptor and refocusing, I did a range of exposures from 30 seconds to 3 minutes, all of the longer ones trailing, and some of the 30 second ones trailing also. I detrailed all the trailed ones using the filter manually in Paint Shop Pro 7 just as jpegs, and ran them through Deep Sky Stacker. I was struck with the beauty of the resulting picture that appeared in front of me. And when I processed them in PSP7 I was stunned with the result. DSS selected 18 exposures, most 30 seconds, 3 of about 70" and 2 about 3', but equivalent to ~30" because of the detrailing process, of which it took an adaptive weighted average. Thor's Helmet, NGC 2359, is 7ยบ from Sirius and exists because of a frantic massive star, called a Wolf-Rayet star near its centre. There is Oxygen O III (or O2+) emission in the centre and Hydrogen clouds further out.
"As I do astronomy on a budget" That may be so, but it doesn't stop you from having a go. I'm amazed with this Thor's Helmet I always thought it was too low in the sky for me.
ReplyDeleteYour enthusiasm shows through your blog, well done.
Dave