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Lion Nebula SH2-132 - RC71

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Posts Made By: Jim Thommes

August 22, 2007 03:28 AM Forum: CCD Imaging and Processing/Deep Sky

First DSO images

Posted By Jim Thommes
Congrats on the first images Brian. My advice is to keep them - you will alwys want to look back on the first ones.

I'm looking forward to seeing more.

Jim Thommes

August 22, 2007 03:35 AM Forum: CCD Imaging and Processing/Deep Sky

Interrupted Images

Posted By Jim Thommes
Cool images Dan!

I like IC983 - its a cool object I will put on my list for next year.

August 22, 2007 03:45 AM Forum: CCD Imaging and Processing/Deep Sky

Stephan`s 5er

Posted By Jim Thommes
Dietmar,
Nice image!

I particularly like the wider framing with NGC7331 in the image.

August 23, 2007 05:21 AM Forum: CCD Imaging and Processing/Deep Sky

Sigma Scorpii and Sharpless 009

Posted By Jim Thommes
Eric, Larry,

Thanks for the comments.

August 26, 2007 09:40 PM Forum: CCD Imaging and Processing/Deep Sky

NP 127is First Light-M8, M20

Posted By Jim Thommes
David,
Ooh, very nice. I can't wait for you to do more with it either - looking forward to more.

August 28, 2007 03:55 AM Forum: CCD Imaging and Processing/Deep Sky

comparing 2.1 hours vs 7.8 hours exp.time

Posted By Jim Thommes
Dietmar,
Yes indeed this is an interesting comparison. (Great images BTW).

I know that the reducer, camera were different as were the conditions and processing, but I wonder if total exposure time tells the whole story. I believe you are saying that there were 2,4,6 minute subs in each example. In the 7.8 hour example there are just more?. Are they in the same proportion?

I am interested because if they were the same times on subs, I would expect the same depth and just less noise with more subs. What would be interesting would be to keep the # of subs the same but increase the time with each of the subs. In this case I would expect more depth *and* less noise (unless light pollution would be a factor.

Richard, I would be interested in seeing any of your work ups on S/N particularly as it relates to # of subs, sub exposure time, camera read noise, and total exposure time.

August 28, 2007 04:11 AM Forum: CCD Imaging and Processing/Deep Sky

Cedrblad 214

Posted By Jim Thommes
Thanks all for your comments...

Ivan, I'm OK with the Rini. I works kinda nice with the refractor for center sharpness, but... See below...

Eric, Dan, Yes, the edge star shape distortion is the reducer, So I'm not sure the optimal distance on the reducer (not even sure I remember where I got it). It's a short focal length reducer. Focus is dodgy in a not so flat field. Seems like it's got a small imaging area - the good news is that my CCD is small.

This is a 0.62x reduction. Maybe I should try that 0.67x AP reducer?

August 30, 2007 04:38 AM Forum: CCD Imaging and Processing/Deep Sky

Omega Nebula Ha

Posted By Jim Thommes
Nice Greg! The Ha line is always a good study with the moon full.

September 2, 2007 12:58 AM Forum: CCD Imaging and Processing/Deep Sky

Eagle Nebula

Posted By Jim Thommes
Nice Greg,

I like the pillars area - particularly the color tonal differencs. It is really plesent to view and shows better then a monotone red seen in many Eagle images.

September 3, 2007 10:19 PM Forum: CCD Imaging and Processing/Deep Sky

NGC7635

Posted By Jim Thommes
Bob,
Must be nice to have everything back together in the observatory. I envy you having one - all my sessions are "pack it up and head to the site".

Nice image. My monitor may be a bit dark, but when I brightened it up, a lot of nice detail came out on your Bubble.

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