M81 M82 CCD and DSLR - colour

[tooth_dr]

I combined all my CCD data (mixture of lum and red) with 1 hour of Canon 40d data I found on the laptop.

 

Here is the result, about 8.75 hours of data.

The colour mottling from the colour data is a bit distracting but I'm out of ideas, probably just a pure lack of data.

 

 

[fireballxl5]

great image tooth_dr!

For my noisy 40D images I've found that the manual RGB noise control in DxO Optics Pro is very effective. 

HTH, Andy

[tooth_dr]

2 minutes ago, fireballxl5 said:

great image tooth_dr!

For my noisy 40D images I've found that the manual RGB noise control in DxO Optics Pro is very effective. 

HTH, Andy

I’m not at all familiar with that. Thanks for sharing your tips Andy ??

[Sunshine]

That's really nice!

[Stardust1]

Well done! Nicely processed!

[carastro]

Looks very nice - I like that.

Carole 

[pipnina]

One of my favourite object pairs, and a lovely image of them at that!

Well done 

 

[bob-c]

A smashing pic .

Bob.

[tooth_dr]

Thanks so much guys and girls for taking time to comment.  I've found another few RGB subs on my laptop from my DSLR, and randomly I've found a few hours worth in H-alpha from my DSLR on it too?!?! I'll try to add the RGB, and then work out what to do with the H-alpha, I must have had a plan way back when I imaged it.

 

[carastro]

Yup, M82 REALLY benefits from Ha, all those Ha jets coming out the side of it. 

Carole 

[fireballxl5]

which scope was used?

[tooth_dr]

38 minutes ago, fireballxl5 said:

which scope was used?

An ED80 with 0.85x FR

[Xiga]

On 03/01/2019 at 23:08, tooth_dr said:

I combined all my CCD data (mixture of lum and red) with 1 hour of Canon 40d data I found on the laptop.

 

Here is the result, about 8.75 hours of data.

The colour mottling from the colour data is a bit distracting but I'm out of ideas, probably just a pure lack of data.

 

 

Very nice Adam. 

You're not alone in having colour gradients on this one. IIRC, i too also had to fight the same issue when i imaged this last year. I'm struggling to remember now, but i also think i discovered that using one of Noel's actions made the problem worse. It could have been one of the banding reduction actions, but don't quote me on that! A good idea is to regularly do a quick Image-Adjustments->Equalize every now and then. It really helps to show up any hidden issues, such as gradients or large scale mottling. 

In general though, I find Photoshop's Camera Raw filter very good at dealing with Colour mottling. If you apply a setting of around 15 for Colour Noise and crank the Colour Smoothing up to 100, you should get something like the version below, which has most of the colour mottling removed. Note though, whenever i use this filter, i usually do an Inverse Star Selection first, just to make sure it doesn't inadvertently affect the colour of any small stars. A layer mask is also a good idea too, so you can exclude the impact from any areas that don't need it. But it's a great filter, and i certainly wouldn't be without it. 

And if you don't mind some CC, if it were me, i would probably also crop out the bright star that's just creeping in at the bottom, as it's a bit distracting (it just makes my brain think 'Amp Glow', even though i know it's not, lol). And i would also have a play with applying some subtle sharpening to each galaxy. i.e try sharpening the small-scale details in M82, and then do the medium to large-scale details in M81. 

[tooth_dr]

14 hours ago, Xiga said:

Very nice Adam. 

You're not alone in having colour gradients on this one. IIRC, i too also had to fight the same issue when i imaged this last year. I'm struggling to remember now, but i also think i discovered that using one of Noel's actions made the problem worse. It could have been one of the banding reduction actions, but don't quote me on that! A good idea is to regularly do a quick Image-Adjustments->Equalize every now and then. It really helps to show up any hidden issues, such as gradients or large scale mottling. 

In general though, I find Photoshop's Camera Raw filter very good at dealing with Colour mottling. If you apply a setting of around 15 for Colour Noise and crank the Colour Smoothing up to 100, you should get something like the version below, which has most of the colour mottling removed. Note though, whenever i use this filter, i usually do an Inverse Star Selection first, just to make sure it doesn't inadvertently affect the colour of any small stars. A layer mask is also a good idea too, so you can exclude the impact from any areas that don't need it. But it's a great filter, and i certainly wouldn't be without it. 

And if you don't mind some CC, if it were me, i would probably also crop out the bright star that's just creeping in at the bottom, as it's a bit distracting (it just makes my brain think 'Amp Glow', even though i know it's not, lol). And i would also have a play with applying some subtle sharpening to each galaxy. i.e try sharpening the small-scale details in M82, and then do the medium to large-scale details in M81. 

 

Thanks Ciaran.  That star is unfortunately NGC3077, with using data from lots of nights and cameras, I've managed to lose it due to different placement and sensor sizes.  It doesn't look great though so best cropped out.

So I found a bit more data from my DSLR (about 26 hours worth in RGB and Ha in 300 and 600s subs, although 90% affect by the moon which is maybe why I didn't do much them before!)  The Ha has brought out the little globules in M81 and the jets in M82.

Here is a quick version, wifes out so I'm here with the kids so have no time to process this.

 

 

 

[fireballxl5]

Although the extra data has greatly improved the background I still really like the colours in your first version of this image. Seeing your post prompted me to have another go with the 11.5 hours of data of the same area using my 85mm/f5.3 refractor and mono CCD. Unfortunately I have only Ha (4 hours) and RGB (2.5 hours each) with no lum. I'm finding that using the Ha as L gives a very noisy image - with hindsight I should of got some lum? but it was early days in my experimenting with HaRGB imaging.

So now I'm trying to create my first synthetic lum...

CS, Andy

[Taff]

Nice work Adam' with the Galaxies so clear with you nice details.Mark

[sloz1664]

Nice image and has Carole has pointed out Ha benefits this image, M82 in particular.

Steve

[tooth_dr]

2 hours ago, fireballxl5 said:

Although the extra data has greatly improved the background I still really like the colours in your first version of this image. Seeing your post prompted me to have another go with the 11.5 hours of data of the same area using my 85mm/f5.3 refractor and mono CCD. Unfortunately I have only Ha (4 hours) and RGB (2.5 hours each) with no lum. I'm finding that using the Ha as L gives a very noisy image - with hindsight I should of got some lum? but it was early days in my experimenting with HaRGB imaging.

So now I'm trying to create my first synthetic lum...

CS, Andy

Thanks Andy. My Ha is rubbish but adds a bit I think. 

The 1 hour of RGB subs from the DSLR in the original version is a much nicer colour as you have mentioned. I can’t seem to achieve that same colour balance in PS with the additional data but this is down to my lack of processing talent, and the moon being present in those subs, and possibly a CLS filter. I can’t remember exactly though 

[tooth_dr]

I don't want to knock @Rodd off the title ? so this will be my last reprocessing attempt at this until I get another few hours luminance.

I've attempted to improve the colour of the galaxies, sharpened things up a bit with masks, and even out the background.  If you don't zoom in too much and sort of squint a bit, it doesn't look half bad.

 

Best wishes

CS

Adam.

 

 

[Rodd]

10 minutes ago, tooth_dr said:

don't want to knock @Rodd off the title ?

Great image Doc!  I do not understand the reference, though.  But the image is very nice.  I see a slight greenish fringe to some of the satrs.  If you use PI, try inverting the image and using SCNR green.  I have had pretty good luck with image inversion in removing star rims and halos.

Rodd

[tooth_dr]

1 hour ago, Rodd said:

Great image Doc!  I do not understand the reference, though.  But the image is very nice.  I see a slight greenish fringe to some of the satrs.  If you use PI, try inverting the image and using SCNR green.  I have had pretty good luck with image inversion in removing star rims and halos.

Rodd

Thanks for the tip Rodd. I don’t use PI but I’ll try HLVG in PS.