M51 Whirlpool Galaxy - now with added colour (Atik 490ex)

[x6gas]

I could get to like this camera...

So last night was clear enough to grab some RGB data of M51 to add to the luminance that I captured earlier in the month. I sometimes find that the colours are pushed a bit hard on some galaxy images I see, so hopefully I haven't gone too mad on this one.

I'd not had much joy combining the separate RGB data using AstroArt and have previously always done it in Photoshop or PhotoPlus but inspired by Olly Penrice I tried again having registered the frames in RegiStar and I'm impressed with the results. Pretty easy; I just did the Tricolor combine in AA5, hit the automatic white balance, and imported to Photoshop to do the LRGB. Simples.

I suspect Olly would prefer it had I not binned the colour, but I don't have his skies so I followed the advice from Steve Chambers in a couple of Sky at Night magazine articles (Sky at Night, March 2012 #82 & September 2011 #76) which led me to bin the colour 3x3 - yes 3x3 - and have the green channel 125% of the red, and blue 150%. This camera copes with 3x3 binning easily.

I have struggled to get good results with RGB images in the past, but Steve's method seems to have worked for me and I am very chuffed with the results.

Data: L = 31 x 300s (binned 1x1); R = 25 x 100s (binned 3x3); G = 25 x 125 (binned 3x3); B = 25 x 150 (binned 3x3)

Scope: 11" EdgeHD with Optec Lepus 0.62 focal reducer

Mount: CGEM DX

Camera: Atik 490ex

Guiding: QHY IMG0H, Atik OAG, PHD

I am capturing a bit more luminance and also some Ha to see the impact, so potentially not finished yet, but very happy with this one! That said, as always comments and suggestions for improvement very welcome.

[Dave Smith]

That is a wonderful image. I'm seriously looking at the 490 EX it seems an excellent camera.

Dave

[x6gas]

Thanks Dave - your images are awesome!

And I meant Steve Richards in the initial post, not Steve Chambers. How embarrassing...

[Oily]

Superb image,loving the detail,something to aspire too aswell

[Beulah]

Very nice.

It's fantastic seeing the images pouring in again after such a terrible year of weather.

[swag72]

This is looking very nice indeed - I am a bit of an advocate of not binning, but you have certainly shown that it can work well. Smashing shot!

[x6gas]

This is looking very nice indeed - I am a bit of an advocate of not binning, but you have certainly shown that it can work well. Smashing shot!

It seems to work with this combination of kit, Sara. The RGB alone is actually quite respectable IMO; I'll post that when I get a moment...

[Chris]

Thats a beautiful shot lovely detail

[morimarty]

This M51 as a lovely 3d look about it. very well done!

[x6gas]

Thanks Chris, thanks Martyn.

Funnily enough I had a quick look at this at lunchtime today and on my screen at work it looked absolutely awful - colours were terrible and too green... but it looks ok on my laptop and iphone...

[andyo]

That's a fantastic image very nice colour

[RobH]

Lovely colour balance and detail.

With pixels as small as the ones used in the 490, binning 3x3 makes sense, although I tend to be an advocate of not binning when you're not limited by seeing conditions.

I think the image will be improved a lot by not pushing the blackpoint so high though, as there's lots of faint and interesting detail in this FOV that's currently being lost.

Don't make your space quite so black and the image will immediately gain greater depth.

Cheers

Rob

[x6gas]

Lovely colour balance and detail.

With pixels as small as the ones used in the 490, binning 3x3 makes sense, although I tend to be an advocate of not binning when you're not limited by seeing conditions.

I think the image will be improved a lot by not pushing the blackpoint so high though, as there's lots of faint and interesting detail in this FOV that's currently being lost.

Don't make your space quite so black and the image will immediately gain greater depth.

Cheers

Rob

Thanks Rob - and ah yes, you've caught me!

You'll see the hour at which I posted this originally - I'd had a hiccup with RegiStar and didn't really do any processing. The luminance suffers from a couple of dust bunnies and I had whacked the blackpoint way over to kill them. I was a bit surprised at how good the result looked on my laptop, but as mentioned above it actually looks terrible on my monitor at work...

Anyway, this is the other end of the scale with no levels adjustment:

[x6gas]

And here it is with a more sensible levels adjustment, but being careful not to clip the blackpoint.

[sologuitarist61]

Stunning image!

[Gina]

Marvellous detail in that image I have a dust bunny in just about the same position

[Ewan]

They are breeding as i saw 2 on my images last night.

Terrific images Ian, over stretching does 'hide' a multitude of 'errors' at the expense of detail, i am guilty of the same thing mind.

I'd probably go with a stretch in between the last & 1st image, just a thought, the Spot Healing Brush in PS might help with the dust bunnies to an extent.

Will you be adding more data to this or do you think it's about there Ian ?

[x6gas]

Many thanks Richard, Gina (my inspiration!), and Ewan.

I am enjoying my galaxy hunting with the Big Cat...

Will you be adding more data to this or do you think it's about there Ian ?

I will Ewan. In fact, I have 2 more hrs of luminance and some Ha in the can. Just need to process it! After months, and months of cloud three clear nights on the spin and I have more data than I can process and I've been working on the M81 data I captured last night... Sneak preview:

[swag72]

That M81 looks very tasty indeed - I'm looking forward to seeing that one!!

[Gina]

Oh yes, very nice indeed

[Ewan]

That's going to be a korker Ian can't wait.

[ejwwest]

_{Wonderful pictures. Makes me conclude there's not much point in persisting with my DSLR and freeware!}

[RobH]

Hope you don't mind but I removed the dust bunnies and tweaked the background levels a tad.

The bunnies were removed using the clone tool in photoshop with the mode set to 'lighten'.

Hold down 'alt' and click on the background and simply paint the offending bits out. As long as you don't sample something like a star, this works well.

With the mode set to lighten, it doesn't affect anything brighter than the sampled area, so you don't need to worry about it affecting the stars etc.

Cheers

Rob

[x6gas]

That M81 looks very tasty indeed - I'm looking forward to seeing that one!!

Oh yes, very nice indeed

Thanks both - yes, coming along nicely. This M81 is actually with my 460ex as I am having dust trouble with the 490 (think it's going to have to go back to Atik for cleaning...)

It's 2 hours worth of luminance and I need at least that again, plus the colour. I thought I'd have a go at processing what I have though; there was some advice on SGL a while ago about different targets and different data responding in different ways to processing so it's useful to run through the data to help my learning curve...

[x6gas]

Hope you don't mind but I removed the dust bunnies and tweaked the background levels a tad.

The bunnies were removed using the clone tool in photoshop with the mode set to 'lighten'.

Hold down 'alt' and click on the background and simply paint the offending bits out. As long as you don't sample something like a star, this works well.

With the mode set to lighten, it doesn't affect anything brighter than the sampled area, so you don't need to worry about it affecting the stars etc.

Cheers

Rob

Thank Rob - I am processing this again with the full five hours of Luminance that I now have so the tip about cloning with blend mode on lighten is really well timed. And thanks for cleaning up the image - looks much better .