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ngc7023 iris


alacant

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Shot with a Canon 700d. 120min.

Hi everyone. I knew this was faint and so working on that basis, decided upon two hours over my usual one. Disappointing. Over 2 hours, the red nebulae around the same area would be vibrant. I had a similar problem processing m78 -IIRC similar colours- back in December. I wonder if it's the Canon sensor which is not as sensitive where light is reflected? Has anyone any tricks or tips for this one? Thanks for looking and clear skies.

iri3.thumb.jpg.06852034190ad69694ad1e1038305b99.jpg

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The core of the reflection nebula in this is excellent. You've held the central star down superbly and let the bright blue nebula show its detail. Overall the image is colour-cold to my eye, lacking red signal. How about a lift of the mid point in levels, red channel? There are some subtle reds in the main nebula but they are very faint and will need both time and attention.

Olly

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I'm not sure if there is any secret sauce, other than the usual thing about more subs.  When I did this a Olly's place using his skies, scopes and CCD cameras, we gathered >18 hours of data in 15 minute subs.  Two hours is pretty frugal.

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I think the nebula looks good. I like seeing fellow DSLR imagers results.

As far as the red is concerned... is you Canon astro or full spectrum modded? if not that that is the reason for your lack of red signal data. Once it is modded, you'll find a lot of red data in your images.

 

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Are you post processing with Startools by any chance?  If so, then it might be worth winding down the red reduction slider in the colour module.

I found this a rather challenging DSLR target last year, been meaning to go back when it comes back into view from my garden, be interested to see how you get on with more subs?

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Hi everyone and thanks so much for your time.

21 hours ago, ollypenrice said:

a lift of the mid point in levels, red channel

Yep, I had a look at some other snaps and also the dust around seems brownish. Here's your suggestion. I think there's an improvement but OMG that middle slider is a nightmare; it's so easy to overdo it. The only way I could control the amount was side by side comparison. 

 

iri3-rojo.jpg

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21 hours ago, gnomus said:

we gathered >18 hours of data in 15 minute subs.  Two hours is pretty frugal.

Hi. Yeah, I'm trying to get my head around this time thing so it's comforting to know that if I ever do have the patience, that's a certain way to improve.

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20 hours ago, MarsG76 said:

is you Canon astro or full spectrum modded?

Hi. It's a 700d which has been modified; it can and does take red hydrogen snaps OK. Exactly which modification has been made, I'm not sure. I don't think it's full spectrum since a daytime snap doesn't show any ir effect. 

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1 minute ago, alacant said:

Hi. Yeah, I'm trying to get my head around this time thing so it's comforting to know that if I ever do have the patience, that's a certain way to improve.

No worries.  I have no patience - that is why I am convinced that large(-ish) amounts of data are a good idea.  If the processing game is all about teasing ultra faint signal from the dark and noisy shadow areas, then more subs -> less noise -> easier to drag out the faint stuff -> easier time processing.  When I was doing the 'imaging in a night' thing, I would often find myself spending hours and hours attempting to deal with noise - often with limited success.  Now obviously these things suffer from the law of diminishing returns, plus it may not be feasible to gather 40+ hours in the UK (one image per year??), but you may be surprised how much simpler things become if you start to get near to double-digits of total exposure hours.  Well ... perhaps not simpler ... but you can start to concentrate more on aesthetics and less on NR.      

PS: I like the new version :icon_biggrin:

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On 21/8/2017 at 22:29, almcl said:

post processing with Startools by any chance?

Hi. Yes. I love its colour module since it gets you balanced without having to jump through pi hoops! The limitation is exactly the sliders you mention; where in the curve you apply the colour -in this case red- is the problem. For the latter it has to be The Gimp. Cheers and clear skies.

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4 minutes ago, gnomus said:

I like the new version :icon_biggrin:

Yeyyyy. Progress! And thanks for the kind advice re patience. It is me as we have 300+ clear nights per year here in SE Spain. My main issue is the  'there's so much to photograph, I'm never going to finish' attitude. So I end up with loadsa stuff ticked off but few properly finished images. Cheers and clear skies.  

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1 hour ago, alacant said:

Hi. It's a 700d which has been modified; it can and does take red hydrogen snaps OK. Exactly which modification has been made, I'm not sure. I don't think it's full spectrum since a daytime snap doesn't show any ir effect. 

I modded my Canon 40D, but I simply replaced the IR/UV filter with a clear piece of glass and my 40D lets in a phenomenal amount of red/Halpha/SII. Granted that it is quite useless for day time photography.. but it doesn't matter since the 40D is only used for AP.

Perhaps the mod you have still blocks some of the HII??

 

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3 hours ago, MarsG76 said:

number of clear nights

Don't forget though that clear doesn't mean good for ap. Tonight for example, the atmosphere just isn't settling. If not that, it's haze from the onshore easterlies. Even worse, one could run out of cool beer!

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5 minutes ago, alacant said:

Don't forget though that clear doesn't mean good for ap. Tonight for example, the atmosphere just isn't settling. If not that, it's haze from the onshore easterlies. Even worse, one could run out of cool beer!

I can handle and live with everything... EXCEPT for running out of cool beer... that is simply unacceptable. :-D

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That second 'redder' edit is looking good :) Hats off to you for doing this difficult target in such few hours!. I'm working on this one and have 150x600s so far, as I know that my sky conditions aren't great and I need all the help I can get to deal with the noise!!!

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