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M51 - Help needed

Started by smvictor, 02/04/2005 10:40AM
Posted 02/04/2005 10:40AM | Edited 02/04/2005 10:53AM Opening Post
Hi all-

I've been lurking and absorbing your knowledge and am ready to ask for help. This is an image of M51 shot with a 10" f10 on a 6302 chip. It is 36 600 sec lum exposures binned 2x2 and 12 each RGB binned 3x3, 12 hours all together. The image is cropped of course, as the sky noise is overwhelming at full image.

It is shot under very light polluted skies, 7 or 8 on the Bortle scale.

So my question is, is this the best I can do? Can I get rid of the sky noise by better processing? Is the binning hurting me - Should my lum be 1x1? Sould I try again using the IDAS LPS filter? Would 900 or 1200 sec exposures help or just make it worse?

Thanks for any comments.


Attached Image:

smvictor's attachment for post 22016
Posted 02/04/2005 10:49AM #1
Is this an ABG chip (anti-blooming?) If so, this may be the best you will get out of it.

Roland Christen
Posted 02/04/2005 12:42PM | Edited 02/04/2005 12:42PM #2
Hi Steven,
You can find help calculating your subexposures here:
and John Smith has some relevant articles too:
If you're good with statistics, dive into Stan Moore's site.
One would think that with that much exposure time (12 hours) that you could have pulled a little more detail out of your M 51. Did you do a gradient removal?

dan kowall