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Uranium235

Heart of the Heart revisited

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Despite the full moon last night I was determined to get out last night and get something. I started off by getting some subs of NGC6823 (work in progress), while waiting for IC1805 to rise above the house. This year I thought I would try and push the boat out in terms of sub length, so I went with 15min exposures to see if I could rake in any more detail when added to a selection of last years Ha subs with the CG5.

Once processed the difference to last years was noticeable, much better detail. Still a little bit of noise, but thats something I can fix if I throw more 15min subs into the pot. The only other thing i did differently with this is use entropy weighted stacking on the Ha subs, cant really see that much difference between that and sigma clipping.

IC1805: Heart Nebula

ED80 (0.85x), Atik 314L+, NEQ6

22x450 + 9x900 (Ha_L), 16x450 (SII,Ha,OIII)

Setpoint: -10

Thanks for looking :)

Rob

First the Ha:

index.php?app=core&module=attach&section=attach&attach_rel_module=post&attach_id=73539

Then with a dash of classic hubble colour

index.php?app=core&module=attach&section=attach&attach_rel_module=post&attach_id=73540

post-5513-0-94432800-1349037660_thumb.jp

post-5513-0-65570600-1349037769_thumb.jp

Edited by Uranium235
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Brilliant imaging, you've really captured the depth in them, they look almost solid.

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This is one of my favourite parts of the night sky... and you've certainly done it justice! Very nice indeed Rob...

If you want to try something different with this, try mapping Ha to Red, OIII to blue and synthesising a green channel from the two - Of course it's another false colour version, but if you're bored and want to spend a cloudy night doing in a bit of processing practice. then the result's quite interesting and worthwhile...

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Thanks guys :)

Andy, I'll give the HOO version a shot later on. From what I remember there isnt an awful lot of OIII in this and it might get dominated by the Ha. I might be lucky here and get some clear sky tonight so I could chuck at least another 12x900 on the pile and take it up to 8 hours of Ha.... yummy!

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Nice data there and a cracking image, well they both are. I personally do really like your framing - Nicely done!

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There's a lot going on in this region of space. It's fascinating to look at and this image does it full justice.

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Ooh nice one Rob, cracking detail! I think your new mount's capabilities have given you much sharper images.

Have any trouble maintaining detail in the brighter areas when processing? I did, but then that was with my DSLR data which won't have the same dynamic range, which may make it trickier I guess.

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Ooh nice one Rob, cracking detail! I think your new mount's capabilities have given you much sharper images.

Have any trouble maintaining detail in the brighter areas when processing? I did, but then that was with my DSLR data which won't have the same dynamic range, which may make it trickier I guess.

Funny you should mention that because I to knock it down and start again a couple of times because I overcooked the central portion of the nebula when chasing the wispy bits. Maybe the entropy weighted stacking did actually do something. DSS doesnt explain it all that much, all I know is that its for objects with a high dynamic range but you need a shedload of subs to make it work properly. Still, it was a good result for something where I'd used no calibration at all :) (apart from a hot pixel cleanup)

With the DSLR you might always struggle because IIRC you only get just over 4000 levels of brightness at ISO800 (its 64000 levels with a 16bit CCD), which is going to present problems when working on objects that have very bright and very dim areas. Maybe the way round this for you is to compost a couple of layers (like you would with M42)?

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Funny you should mention that because I to knock it down and start again a couple of times because I overcooked the central portion of the nebula when chasing the wispy bits. Maybe the entropy weighted stacking did actually do something. DSS doesnt explain it all that much, all I know is that its for objects with a high dynamic range but you need a shedload of subs to make it work properly. Still, it was a good result for something where I'd used no calibration at all :) (apart from a hot pixel cleanup)

With the DSLR you might always struggle because IIRC you only get just over 4000 levels of brightness at ISO800 (its 64000 levels with a 16bit CCD), which is going to present problems when working on objects that have very bright and very dim areas. Maybe the way round this for you is to compost a couple of layers (like you would with M42)?

The Canon EOS 1100D and others with the new Digic 4 image processor give 14bits = 16384 levels. Yes, Digic 3 cameras like the 1000D give 12 bits = 4096 levels.

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Fantastic detail Rob, The Ha has come through lovely,

The processing is a work of art.

Well woth the time and effort,

Well done Paul

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The Canon EOS 1100D and others with the new Digic 4 image processor give 14bits = 16384 levels. Yes, Digic 3 cameras like the 1000D give 12 bits = 4096 levels.

Thanks for the update Gina, I was unaware Digic 4 processors existed :) those two extra bits give you quadruple the levels, nice. Taking that into account, a 1100d @ ISO400 on an F4 newt might make for something quite interesting.

Also thanks to all who have commented, I'll try to get out tonight in an attempt to beat down the noise a bit more. Will update if I get anything.

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Lovely image Rob, very 3d...cracking capture and processing :smiley:

Cheers

Rob

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Cheers Rob & Jamie. I had no luck in getting out last night as the sky wouldnt stay clear for long enough to make long subs possible. Fortunately, this will be around for quite a while yet so theres plenty of time left to put the icing on the cake :p

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Thanks Neil, thats exactly what I intend to do tonight. The forecast says clear from 7pm, but it wont rise above the house until 9pm so I will find something else to pick on in the meantime. Ive viewed it on another monitor now and I can see the noise. Another 10x900 might do the trick.

Rob

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