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scitmon

Pixinsight help - galaxy vibrance?

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Hello, I've just started using a trail license for Pixinsight and going through some tutorial videos and applying what I'm learning to some data on m81/82 I shot last weekend.  Its all going quite well except that i'm not sure how to get the vibrance I see in other peoples images.

This is mine:

https://astrob.in/346588/0/

I would like is something more along the lines of:

https://goo.gl/images/eEaZGU

Perhaps I'm being unrealistic?  Would really appreciate any tips!  I've attached the tiff file if anyone wants to look at it.

m81 attempt 1.tif

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I don't know if this helps, but here is a light touch up in Gimp 2.9.

5af75b6c293a4_m81attempt1.thumb.jpg.d8290957b4d3e3aad29988c61f7640fe.jpg

Only two things applied:

1. Filters / Nik collection / Color FX pro - remove color cast - removed red cast from the image

2. Slight curves adjustment to boost brightness (and perceived saturation) in bright regions and push background to darker (closer to black than it was) - again perceptual thing - colors tend to look washed out on grayish background, while black one tends to accentuate color and saturation.

What seems to me to be a main issue is white balance. Too much red in the image (probably due to camera sensitivity in that part of spectrum, maybe astro modded camera?). I know Pixinsight has some sort of star based color matching - might give that a try and see what sort of white balance it produces.

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I might be totally wrong here.... but the 'vibrant' images that make my DSLR attempts look a bit flat,usually come from very sensitive mono LRGB composites with a bit of H-aplha thrown in to bring out detail (spiral arms for example...)

 

 

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8 minutes ago, vlaiv said:

I don't know if this helps, but here is a light touch up in Gimp 2.9.

5af75b6c293a4_m81attempt1.thumb.jpg.d8290957b4d3e3aad29988c61f7640fe.jpg

Only two things applied:

1. Filters / Nik collection / Color FX pro - remove color cast - removed red cast from the image

2. Slight curves adjustment to boost brightness (and perceived saturation) in bright regions and push background to darker (closer to black than it was) - again perceptual thing - colors tend to look washed out on grayish background, while black one tends to accentuate color and saturation.

What seems to me to be a main issue is white balance. Too much red in the image (probably due to camera sensitivity in that part of spectrum, maybe astro modded camera?). I know Pixinsight has some sort of star based color matching - might give that a try and see what sort of white balance it produces.

You are correct, it was taken with a modded Canon 700d.  I have used the colour matching tool already but with the galaxy as the target.  Perhaps I'll try with the average of all the stars instead.  I'll also check the colour balance settings.  Thanks!

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10 minutes ago, Craney said:

 

I might be totally wrong here.... but the 'vibrant' images that make my DSLR attempts look a bit flat,usually come from very sensitive mono LRGB composites with a bit of H-aplha thrown in to bring out detail (spiral arms for example...)

 

 

Yes you are right, which is why I am wondering if my expectations are too high.  Time will tell.

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.....  with aspirations,  it's always good to aim for the stars      ;)

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3 hours ago, scitmon said:

Hello, I've just started using a trail license for Pixinsight and going through some tutorial videos and applying what I'm learning to some data on m81/82 I shot last weekend.  Its all going quite well except that i'm not sure how to get the vibrance I see in other peoples images.

This is mine:

https://astrob.in/346588/0/

I would like is something more along the lines of:

https://goo.gl/images/eEaZGU

Perhaps I'm being unrealistic?  Would really appreciate any tips!  I've attached the tiff file if anyone wants to look at it.

m81 attempt 1.tif

The image you refer to on google has an integration time of 23 hours, and was taken with an Atik 460 mono camera at -15 ... -25 C. According to the imager, his site is too light polluted to bring out ifn. But if the camera has a large enough full well capacity, it allows longer exposures and collect target photons while light pollution photons also pour in. Luminance was captured at 10 - 15 minutes per frame, Ha at 10 mins per frame.

https://www.astrobin.com/285328/?nc=user

That being noted, I think you can boost your image a bit. The tif you provided was already stretched, but it has a histogram peak that is shifted to lighter values. By bringing the black point in a bit, and carefully adjusting the mid values and colour saturation, you can improve the image. To enhance the galaxies even more, you can do local histogram equalisation. Finish off with extracting a lightness clone and use this (inverted) as a mask. Then desaturate the background.

You can also do more processing in the linear stage, eg deconvolution if the data allows it, and separate luminance and colour noise reduction.

Other things you could try is to create a synthetic luminance by extracting it from the linear colour image. Then process the colour image for best saturation, and the synthetic luminance for maximum detail. Combine with LRGB combination.

 

Goof luck

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Had another attempt, I think this is as good as I can get it for now: 

get.jpg?insecure

If anyone wants to try and get a better result, I've attached the unaltered stacked image.  I've be very interested to see what experienced imagers can do!

 

stacked2.tif

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 M81_M82_LRGB_res.thumb.jpg.f9c27329bf41c32f8be89657e0c74d92.jpg

I tried to keep some of the faint stuff in the background, such as Holmberg IX

Here's the annotated version

M81_M82_LRGB_res_annot.thumb.jpg.9dec697bbd29279f56f05320318bc590.jpg

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Had quick play with Stacked2 in Pixinsight

 

edited-stacked2.jpg

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