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NGC 7000 reprocess


Scooot

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I’ve always had trouble with colours and relied on auto colour balance routines. I’ve been reading about natural colours on www.clarkvision.com on which he advocates the rgb channels shouldn’t be aligned. I suspect this is quite controversial. :) 

Anyway I thought I’d have another go at my NGC7000 to compare. The difference in colour is quite dramatic, there is more detail in the pelican. The background sky is more of a browny/red which is supposedly more natural? The second process was a bit quicker, I didn’t reduce star sizes for example.

I like the new one but I wonder what one others prefer.

5713A04A-B455-42B3-A472-7EB8E0329C48.thumb.png.37367c4883ca223a0717e41191d451b4.png

Orginal

770E0086-0E62-4D1B-B417-ECD5C589A210.thumb.png.79483d8f32077314bc9f759fdba4cb85.png

New process

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I think they're both interesting and great pictures in their own way ?

It's been said many time to me that there isn't any "natural" way to process these pics - we're pushing histograms, colour balance and star reduction all over the place.

It seems we're really just trying to make a nice looking picture without turning it into a cartoon LOL!

However you decide to do that, using the skills we pick up along the way, is the "right" way to process them - as long as you're happy ?

Personally I try to avoid playing with the data too much. One of the things I really like about PixInsight is that I can reproduce processing runs so that I know I'm approaching each object roughly the same way.

This may mean that all my pictures are junk though LOL!

Again, great pictures - and especially this wide field with all the stars etc. 

David

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Hope you don't mind @Scooot but I took your image and set the background to R:G:B - 23:23:23 in the 'Baffin Bay' region of the image and produced a sort of go-between / ccompromise end result. I don't know whether it is right or wrong in terms of colours but it maintains the definition of NGC7000 whilst still leaving the surrounding star field and nebulosity intact.

scoot-ngc7000.thumb.png.3bb22a54f79a2524225a66b5238ddf4a.png

Really like the widefield view of this region.

Adrian

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9 hours ago, David_L said:

I think they're both interesting and great pictures in their own way ?

It's been said many time to me that there isn't any "natural" way to process these pics - we're pushing histograms, colour balance and star reduction all over the place.

It seems we're really just trying to make a nice looking picture without turning it into a cartoon LOL!

However you decide to do that, using the skills we pick up along the way, is the "right" way to process them - as long as you're happy ?

Personally I try to avoid playing with the data too much. One of the things I really like about PixInsight is that I can reproduce processing runs so that I know I'm approaching each object roughly the same way.

This may mean that all my pictures are junk though LOL!

Again, great pictures - and especially this wide field with all the stars etc. 

David

Yes getting to that happy stage is the trick :) The trouble is it’s a moveable feast, & as I read and learn more it changes :) 

I like PixInsight too and I see how a consistent processing method is very attractive, which is what I’ve been doing to date, with various degrees of success. I used Pixinsight’s Photometric  Colour Calibration on the original image, which if I understand it correctly gets a good white balance and equalises the rgb channels. I also used it on the second image but this time moved the black point to the right on the rgb channels individually whilst stretching.

Anyway thank you for your interesting comments.

 

 

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6 hours ago, Adreneline said:

Hope you don't mind @Scooot but I took your image and set the background to R:G:B - 23:23:23 in the 'Baffin Bay' region of the image and produced a sort of go-between / ccompromise end result. I don't know whether it is right or wrong in terms of colours but it maintains the definition of NGC7000 whilst still leaving the surrounding star field and nebulosity intact.

Really like the widefield view of this region.

Adrian

No I don’t mind at all Adrian. I really appreciate you taking the time to do it. The image as you say is a bit of a half way stage and I do like this version. Did you do it on the second image.

I generally only use PixInsight. I do have photoshop elements 11 but I’m not very good with it. So do you now how I’d set the background to 23:23:23 using PixInsight by any chance. I know how to darken the background using a mask but it’d be trial and error to get it to say 23:23:23. I’ve read somewhere this is about 0.07 to .0.09 in PixInsight.

Thanks again for doing this.

 

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54 minutes ago, Scooot said:

So do you now how I’d set the background to 23:23:23 using PixInsight by any chance.

Hello Richard,

I'm afraid I don't although I am sure it must be possible and someone is bound to pop up and tell us both how do to it! And yes, I did it on the second image.

I use both PI and PS and I'm in the camp that feels that when it come to manipulating colour PS is easier than PI. Certainly PI scores when it comes to pre-processing, background extraction, noise reduction and detail enhancement but I like manipulating colour in PS. Olly Penrice advised me on using 23:23:23 as a 'neutral background' and then it seems the only problem is determining which part in a sea of nebulosity should be set to background - if any! Having said that I don't always use 23:23:23 if I feel it detracts from the target I am trying to image.

I certainly feel that if you like the look of it then that is what matters and the wealth of interpretation one sees on this forum is what makes the hobby interesting and educational.

Good luck.

Adrian

P.S. Can I ask what equipment you used to obtain this image?

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Thanks Adrian, maybe I’ll have to get PS as well some time :) 

I used my unmodded canon 450dslr with Samyang 135mm f2 unguided on my star adventurer. I seem to remember I knocked the tripod slightly and noticed the stars aren’t quite as round as they’d normally be for a 90 second exposure. I also took it near Finchingfield for a lovely change, which was very dark with the Milky Way clearly showing, as opposed to my usual light polluted garden. :) 

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4 minutes ago, Scooot said:

Samyang 135mm f2

I've recently bought one of these and I love it! I also have the 85mm but have had a lot of trouble getting the spacing right to use it with either of my Atik cameras. The 135mm alongside my ZS71 and ED90DS give me lots of flexibility in terms of imaging and FoV.

I consider myself very fortunate that I managed to buy PS Extended CS6 on an education license several years ago at a massive saving compared with the list price at the time. I would be very reluctant to enter into the on-going deal they offer now.

Good luck!

Adrian

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Yes it’s a great lens. I’ve also bought this microfocuser which is a great aid (although I didn’t have it for this image). 

http://www.astrokraken.fr/samyang-135mm-f-2-bracket-micro-focuser-a145773756

I’m thinking of buying a zwo asi 071 mc pro at some point but I want to become more proficient with my current setup first.

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That website is a bit 'one true way' for me! Actually his main target is people who insist on blue backgrounds to night images - which I hardly ever see!

What it also ignores is that white balance changes with position in the sky. Look at a set of RAW daylight images and see how much colour correction they need to look natural.

I'm with Adrian on this one.

Normally I mask off any nebulosity and big stars and then use Gradient exterminator to do automatic background equalisation on the rest of the image. I find that doing this then allows me to 'develop' far better star colours.

With the 'Peli-Nan', especially close up, the problem is lots of nebulosity in the surrounding area and I think Adrian's approach of finding a dark patch works best.

 

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2 minutes ago, Stub Mandrel said:

That website is a bit 'one true way' for me! Actually his main target is people who insist on blue backgrounds to night images - which I hardly ever see!

What it also ignores is that white balance changes with position in the sky. Look at a set of RAW daylight images and see how much colour correction they need to look natural.

I'm with Adrian on this one.

Normally I mask off any nebulosity and big stars and then use Gradient exterminator to do automatic background equalisation on the rest of the image. I find that doing this then allows me to 'develop' far better star colours.

With the 'Peli-Nan', especially close up, the problem is lots of nebulosity in the surrounding area and I think Adrian's approach of finding a dark patch works best.

 

Thanks Neil,

Yes I like Adrian’s rendition the most as well although that image doesn’t have equal rgb channels either. 

I have actually tried processing daylight pure raws with PixInsight and found it very difficult to get the correct white balance. The best way I found was to cheat a bit and change the pure raw setting to using the camera white balance. :) 

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2 hours ago, Adreneline said:

Looking good! Was that in PI?

Adrian

Yes. I took the red image and more accurately aligned the individual RGB channels at the beginning of the data. I then moved the mid slider of the green slightly left which gave a more golden hue but also gave it a green cast. I removed this with PI’s SCNR. Colours then seemed good so I created a range mask and darkened the background a bit.

Here’s the before and after histogram.

B85B28F9-38BC-483C-8E97-E9E3154A7E9A.thumb.jpeg.fdf6f91d4de1d28164c94b9dc3abb4b3.jpeg

before

D75AF192-9CF7-4C8B-BE03-EE1754E75266.thumb.jpeg.d52ab4b27a6e9af898c13b454a94dc85.jpeg

After

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