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Old 12-11-2013, 10:06 PM
bloodhound31
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Having a real hard time processing.

M78
27 images of 8 minutes.
Tracking and focus good.
10 darks.

Aligning and stacking in MaximDL5 as it was the capture program as well.

I've tried median, average and sum stacking, exported as a 16bit TIFF and played in photoshop.

It just looks like CRAP! No matter what I do, I can't seem to bring out the nebulosity without blowing out the colours and MASSIVE amounts of grain.

Quite frustrating really.
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  #2  
Old 13-11-2013, 01:00 AM
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alistairsam
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Hi,

Can you post a link to one or two of the subs as well as the stacked one?
what camera did you use? mono or colour? dslr or ccd? baht mask left accidentally on?

Cheers
Alistair
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Old 13-11-2013, 10:40 AM
bloodhound31
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Quote:
Originally Posted by alistairsam View Post
Hi,

Can you post a link to one or two of the subs as well as the stacked one?
what camera did you use? mono or colour? dslr or ccd? baht mask left accidentally on?

Cheers
Alistair
Hi mate. Here is the stacked final image. With one look I know it could be much better.

Later tonight I'll grab one of the RAW mono FITS in MaximDL5, screen stretch it and take a screen shot, then I'll colour convert it and take another screen shot.

I really need help here because for all the images I turn out where people say, "WOW", I know I could do better if I wasn't just guessing what processing software can do.

Baz.
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Old 13-11-2013, 04:00 PM
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First of all you have a bad coloured gradient. Did you take flats? If the gradient is removed, the colour comes out a lot better. Thumbnail shows the (stretched) gradient. I can also post a thumbnail of your image with the gradient removed if that's OK with you.
Geoff
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Old 13-11-2013, 04:35 PM
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This is a very dim object. I took over 15 hours of data on M78 and it still contained noise which I had to smooth out. I was taking 20 minute subs in the Luminence and that should have been something like 30 minutes or even 40 minutes. 16 minutes will show the brighter regions but not the darker areas. Stretching will always bring out the noise. Longer subs will help you.
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Old 13-11-2013, 05:04 PM
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Quote:
Originally Posted by Paul Haese View Post
This is a very dim object. I took over 15 hours of data on M78 and it still contained noise which I had to smooth out. I was taking 20 minute subs in the Luminence and that should have been something like 30 minutes or even 40 minutes. 16 minutes will show the brighter regions but not the darker areas. Stretching will always bring out the noise. Longer subs will help you.
However, you can still get a pretty decent pic with shorter exposures and less time. This one was 10min exposures over 3 hours with a 4" refractor, so I think the OP has more issues than just his exposure time of 3.6hrs.
http://www.astrobin.com/27709/
and yes, there is a lot of noise.
Geoff
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Old 13-11-2013, 05:12 PM
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Yes but that image was taken from a dark sky site too. Light pollution makes this image even harder to image.
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Old 13-11-2013, 11:59 PM
bloodhound31
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Thanks guys. I used a gradient layer to remove the gradient so obviously that didn't work. I'm thinking that perhaps there may have been some smoke in the atmosphere from all the fires and even though I couldn't see it, perhaps there was enough to affect the image? Dunno.

I'll try to go for longer exposures of 20 minutes and see how that goes, now that all the fires are out.
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Old 14-11-2013, 05:28 PM
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10 min subs 4hours total TEC180 at a dark site, Proline 16803 camera 60% QE. No noise.

http://www.pbase.com/gregbradley/image/108830707/large

Its a large APO though, sensitive camera, very dark skies and reasonably good seeing.

The best resource for image processing how to's is Adam Block DVD tutorials. Well worth the money. He has some new ones
out. I ordered one of them. I should have it soon.

Greg.
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