M31 Reprocess

[Rex]

Hi Everyone, this is another one that was taken on the 27 & 28 Oct, while chasing clouds around my imaging targets. You can tell it's starting to get warm up, up this way, the colour noise in the background is unavoidable at this time of year. Won't be long and the wet will be here and then I'll do a cooling mod. Next year should be a ripper.

Image details:
26x300sec @ ISO1600 with the gear in my signature.

Larger version here: http://www.astrobin.com/full/134753/0/

Edit: Ok folks, after Al's reprocess and guidance with the tutorials he posted, I had another go at processing this one. I have attached it to this post. Although I do have photoshop, these days I tend to process all my images totally with pixinsight. PI doesn't have rope selection tools or the like because when you use these tools, you are manipulating the data it an unnatural way, meaning doing something to a certain structure rather than to all pixels at a particular brightness etc. (I am not criticizing anyone for using these tools, as to highlight some structures you need them). I still prefer Al's repro because he managed to bring the pinks out in the nebula's by using such tools. However I am trying my hand at staying true to the data bla bla bla, so decided not to use them. The attached reprocess is the closest I can come to Al's with my current knowledge using PI. I am sure that with more practice I will be able to get there, but for now this is it. I may have a go using PS later down the track.

Larger version here: http://www.astrobin.com/full/134753/B/

Thanks for looking.

[Geoff45]

Nice image Rex. Pity that it's too low for us Mexicans down south to get a decent image of it.
Geoff

[Placidus]

Very fine, Rex. It looks so close we could reach out and touch it.

[alpal]

Great data Rex,
I would love to have a go at the colours & post a picture here.
I think I could bring out more reds & blues.

cheers
Allan

[Rex]

Thanks Geoff, I know what u mean, there are quite a few Northern Obje ts that I would love to have a go at, but they are too far north even for here.



Thank you Mike, I love the 3D effect this one seems to have.



Thanks Allan. I will load up a dropbox file and post a link. Please share with us exactly what you did so I can replicate it. Not just what procedures you used but also the settings. I post my pictures here to learn how to process them better so specific instructions are most helpful. I'll sort out the link and post it later this arvo. Thanks for your help.

[cometcatcher]

The profanity filters on the forum both electronic and human will not allow me to convey the way I really like the image. So all I can do is say that's very very nice, well done. ;)

I've been wanting to have a crack at this for ages, but would have to carry the scope a long way to avoid street lights and trees. One day....

[Rex]

Thank you Kevin, most appreciated. Thank you also for the laugh. :rofl:

[alpal]

Rex,
Hi Rex,
no need - I just had a quick go at the colours using LAB mode & blurred layer masks
to highlight various areas.
I also used selective colour to make blurred masks & played around with the sliders in Photoshop.
see the result here:

http://www.astrobin.com/full/134829/0/

[Rex]

Hi Allan, mate I really like what you have done, however your explanation of what you did to achieve those results are, well, vague at best. I would really appreciate some more information so that I may try it for myself, after all the best way to learn is to practice.

[alpal]

Hi Rex,
I learnt about blurred layer masks a long time ago.
Check Louie's videos here:
https://www.youtube.com/channel/UCJ5b6pFHBGe66vsuSaXb-0A

There is one on masks & really good one on LAB mode -
to alter colours without affecting brightness.

I also studied the Ken Crawford videos of digging out the detail
& applied it instead to colours.
see here:
http://www.imagingdeepsky.com/Tutorials/MSDLB_Stream/MSDLB_Stream.html

Basically you can select an area with the paint brush on a mask
& do whatever you want with it.
The blurring helps to blend it in to your original picture.
I also use in Photoshop: select, refine mask, to help.
Some would say that it's cheating but Ken Crawford says otherwise.


cheers
Allan

[Camelopardalis]

Lovely Rex, well done :thumbsup: really like the colours coming out there, how do you encourage them? I've got a similar amount of exposure and mine is looking a bit pale, maybe I need to do another repro :lol:

[RickS]

That's a fine M31 from Downunder, Rex!

[Rex]

Thanks very much Allen, quite a bit of studying to do there, hopefully will help improve what I am doing. :)



Thanks Dunk, to increase the saturation I normally use curves, PI has a saturation tab on the curves tool that I use. There is a separate saturation tool as well but I like the curves results better. I just had a look at Allens links above and Louie has some great tips there for photoshop which are very useful. Just have to modify slightly to achieve the same result in pixinsight.

[Rex]

Thanks Rick, I only wish the entire thing had fit in the FOV, oh well can't have everything can we? ;)

[RobF]

Really nice work Rex. Those extra few degrees you get up north will be a boost too.

All you need to do now is find and monitor some Cepheid variables in there perhaps. :question: :D

[phobos27]

Very nice Rex! Love the clarity of the dust lanes!

[strongmanmike]

Yes an excellent M31 from Oz Rex :thumbsup:...and Al's repro is quite good this time :)

Mike

[Rex]

Thanks Rob, unfortunately the heat comes with the location also, neve mind, can't have everything now can we.
Yeah I could do that, I am actually a member of the AAVSO, although it has been a long while since I logged any observations, and they were all visual not photographic.



Thanks Nick, I like that too. :)



Thanks Mike, and yep Al's repro is quite good. I haven't managed to replicate it yet, but I will be trying.

[SimmoW]

Nice one Rex, I like your original just as much as the repro.

[Amaranthus]

Excellent work Rex. That beauty is now below my horizon at 43S (alas!)

[alpal]

Rex,
Thanks Rex,
I wondered what your pic would look like with a further complete LAB mode boost.
This increases the colour without affecting it's brightness.
I then found that the background looked too noisy - full of colour noise
so I used a noise reduction mask - then added noise as well at 2%.
I post the result here:
http://www.astrobin.com/full/134855/0/

Do you like that better?
If so you are welcome to post it or the previous one on Astrobin as yours.
It's only in the staging area now.
I think it's the best M31 ever on Ice in Space - ( after a quick Google search.)
You have great data.

cheers
Allan

[Camelopardalis]

Thanks Rex, will give it a go :thumbsup:

[Rex]

Thanks Simon, I do like my original, but what Al has managed to do was what I was trying to achieve with my original processing. Like everyone, I'm always on the lookout for easier or better ways to do things.



Thanks Barry, I can't wait to do the cooling mod on y camera, it really annoys me all the colour noise in the background. Al seems to have eliminated most of it in his second repro, so will be having a look through the utorials posted earlier. It's something I haven't been able to put my finger on how to get rid of it yet.



Al I really like this rendition thank you very much for the compliments, and I may take you up on the offer of posting it, but I would like to try and replicate it first if that's ok. Especially the elimination of the colour noise. I always struggle with that as soon as it starts to get warm up here.



Your welcome Dunk. I'm looking forward to seeing your repro.

[nebulosity.]

Fair dinkum! Absolutely stunning Rex! Well done on an awesome image :thumbsup:

I couldn't help myself and had a fiddle as well :prey2:, probably wrecked it :lol:

Cheers
Jo :D

[Rex]

Nice effort Jo, thanks. I have attached a reprocess to the first post, I couldn't bring the pinks out like Al has using PI, but it's pretty close.

[alpal]

Rex,
Hi Rex,
you won't be able to get the image like mine unless
you do blurred masks in Photoshop of certain small & large areas.
I know that is not scientifically correct but it does give a more pleasing image.
I started by drawing a mask as a ring around the galaxy.
I could see from other images posted that there you would find all the red nebulas & blue areas.
I then boosted it in LAB mode just for those areas & the colours popped.
Further refinement of the mask using the paint brush at different strengths then highlighted only the areas I wanted.
This mask was then blurred & feathered - & the opacity altered.
I had to do this many times & even mask just many tiny areas in the same way
to get the final result here:
http://www.astrobin.com/full/134855/0/
Maybe I actually overcooked it & perhaps the previous version with
a noise reduction mask on the background would be better?
here:
http://www.astrobin.com/full/134829/0/
Should I fix that version?

cheers
Allan

[strongmanmike]

Al's on a roll here Rex :computer::painting:...great stuff (both of you) :thumbsup:

Mike

[Rex]

Hi Al, yeah I do realise that's what I will have to do to achieve similar results as you. I will probably have a go at it with photoshop one of these days. I am pretty happy with the data as you said, so i want to get the most out of it.



Yeah he's done really well, and taught me a thing or two in the process. Thanks for the encouragent Mike.

[Geoff45]

Nice repro Rex. Don't be tempted with PS. stay true to the data.
Geoff

[Ross G]

Hi Rex,

M31 is my favourite object in the sky and yours is a great looking photo.

I like your original and the repro.

Colour is difficult to get from our latitudes as it is so low.
I have photographed M31 from Coonabarabran and it barely gets to 14 degrees above the horizon so yours is an excellent capture.

Great work!

Ross.

[Rex]

Thanks Geoff, I know what you mean, and for the moment I will do exactly that. Going to play some more in PI when I get some time and try some more elaborate range masks to try and improve it.



Thanks Ross, 14 degrees is very low, you did well to get anything at all. I think I over saturated the repro but it's all a learning curve, and I have some more playing to do with this one before I hang up the mouse.

[tilbrook@rbe.ne]

Very nice M31 Rex!:thumbsup:

Certainly some good tips in this thread.

But....... always do a version you like.:)

Can get confusing with many suggestions.

Cheers,

Justin.

[alpal]

Dear Geoff,
As soon as you stretch the data you are no longer true to it.
Surely the object is to show our eyes what we might otherwise have not seen?

cheers
Allan