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M31 HaLRGB


Rodd

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Hi Rodd

Thanks for making these files available. Gave me a bit of entertainment tonight!  I am not an expert at processing deep sky images and just applied what I know from planetary stuff.  In Photoshop the histogram appears perfectly balanced, so I think the colour is about right.  I didn't do any smoothing/sharpening as the data was so good anyway.   Also, I am looking at two monitors.   One is a consumer monitor, the other is a professional  monitor from work.  When I move the images between the two the difference is night and day.   On my work monitor the background is inky black.  On my "home" monitor the background is a lot lighter with a hint of magenta.  Anyway, let me know what you think.

Cheers

Nick

Rodd M31.jpg

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4 hours ago, Nick Smith said:

Anyway, let me know what you think.

Not bad...yes the histogram for me was almost perfectly balanced without any color calibration.  I think its because there are equal numbers of subs in all channels.  But--very much like my later attempts, the galaxy looks a bit yellowish.  Heck, maybe that is the correct color---after all, Wim and Dave, myself, and now you have rendered a yellowish galaxy.  Did you use wavelet sharpening--like is used in the planetary software?--like...can't think of the name now, but I use it when I do lunar imaging--something I have not done in a while and I miss it.   Anyway--it looks like you may have oversharpened some of the galaxy--not by much though--only noticeable in full resolution.

Rodd                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                

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Hi Rodd

I think the colour is what it is.  I think if you had a load more data the blue stuff on the outside would show a bit more.  I didn't apply any wavelet deconvolution or sharpening-not on purpose anyway! I did apply an action to remove the blue star halos that may have done something.  Who knows??  With lunar and planetary stuff we have a saying that the best data needs virtually nothing doing to it and I think this is the case here.

Cheers  Nick

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But in the end, when all is said and done...I feel that this basically unprocessed HaLRGB image is the best I can do.  This is right after the lum with ha was inserted into the HaRGB.  No processing after that.  So basically an unprocessed image.  Try as I might, I just can't seem to improve on this.  Thanks everyone for the great response--and I am glad you had fun with the data!

Rodd

Image04-SLUM-DECON.thumb.jpg.d67b3a33063f9f40bc8068f254d2c73a.jpg

 

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11 minutes ago, Nick Smith said:

Fantastic Rodd.  All I would do is run it through HLVG, and get rid of the blue halos around the stars.

I only see one halo--the big star at right.  The other [removed word] I think is due to larger blue stars due to poor conditions when shooting the blue.

Rodd

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5 minutes ago, Nick Smith said:

You can get rid of them using Noel's actions.  Something like this Rodd, we are really splitting hairs now,  You should be EXTREMELY pleased with the result

I use PI--Noels thing is PS.  You say I should be happy--I didn't do anything to this image--It was just integrated and combined--awaiting processing.  Its not even an image yet.  My earlier versions are ok.  But not really.

Rodd

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Well, its all down to personal taste Rodd.  You can make it look like a " cartoon" , which I though you were trying to avoid, or accept it for what it is is.  You have some great data where a simple stretch and combine does the job.  I do not see why you would consider it to be "not even an image yet"??

Nick

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And also Rodd, it is possible (in fact probable) we are not even looking at the same thing!  On one of my monitors this looks great (the correctly calibrated LCD from work), on the other it looks a bit overexposed with a bit of a gradient in the bottom left.  In fact, your processed versions look a lot better on this (other) monitor.  The only way to know for sure would be to print the picture out...

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32 minutes ago, Nick Smith said:

I do not see why you would consider it to be "not even an image yet"??

Because I did not process it.  Processing starts at this point.  I was being a bit facetious in truth.  Its an image.  But one that can be made much better.  in time I will.  But I need to step away and do another one and come back to it.

15 minutes ago, Laurin Dave said:

tips on how to improve it to your taste.

That's what this thread has been.  I had a closer look at your image and I think it might be the best of the lot.  I use PI and to change to PS is not really an option.  I know how to use the tools in pi, so I am not sure what anyone can say to help.  Its kind of like shooting a jumpshot in basketball-one knows how to do it--you just have to do it!  

14 minutes ago, Nick Smith said:

The only way to know for sure would be to print the picture out...

I agree.  But I have noticed that a truly great image looks good on any monitor.  I need to take a break from M31 for a while.  I have the data and will return to process it in a few weeks or a month or what ever.  

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I don’t do much in photoshop Rodd as I don’t know how, black point, a bit of vibrancy, saturation and a good look at full screen and above resolution.. and I didn’t really do much in Pi, a small amount of TGV and MMT noise reduction, photometric colour calibration( for that lovely yellow old star colour ? and those lovely blue supergiants) channel combine, stretch of RGB Ha and lum with HT and curves, saturation increase with curves on a range masked RGB, NBRGBcombine to bring in Ha, then got rid of the red cast and over bright Ha with SCNR and a lum mask then LRGB combine then LHE at 120, 1.5, 0.5 then into Photoshop for black point and saturation... one of the  best things I do to improve my images is look at them full screen on my iMac ? which has a great screen. 

Dave

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16 hours ago, Nick Smith said:

I think the colour is what it is

 

15 minutes ago, Laurin Dave said:

which has a great screen. 

Please don't get the impression I am ungrateful....far from it.  I have improved.  I Thank you for your continued interest.  I stand corrected--in the end, here is the version that I think is probably my best all around effort --a few posts back 

 

 

 

Image16a2.thumb.jpg.e7cd11bb3014e9472cdcdf07848d1f9c.jpg

Image16a2crop.jpg.f8650b328d3018b4756abb0b0b7be874.jpg

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3 hours ago, Nick Smith said:

Fantastic Rodd.  All I would do is run it through HLVG, and get rid of the blue halos around the stars.

I think I got it Nick--better?  In PI I created a loosely fitting star mask and applied it to the inverted image then used SCNR red and green to educe halos. Colors ar opposite when reversed, so its a bit tricky.  Seems to work for the most part.

 

 

Image16a2-halos4.thumb.jpg.7936228cdb4c479dd305dc41c2dd85cb.jpg

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1 hour ago, Laurin Dave said:

No impression of that at all Rodd ?.  And that last one is fab...  on another topic its a fabulously clear night here in Berkshire... so dark 

Dave

Then what are you doing looking at the screen man....Image while you can!  

By the way--the last one has a black background--too dark.  I fixed it.  This is it

 

Final3.thumb.jpg.b988368b3ab29bb49b4a313cae13444f.jpg

 

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20 minutes ago, Laurin Dave said:

I am ... M1...  ?

Good...love M1--great target.   Here is my best effort to date-a crop from a 5" refractor image.  LRGB (with a teeny bit of Ha).  I am looking forward to getting this one with the C11Edge

Good luck.

Lwc16OfuCuAn_1824x0_Mjc8P1T1.thumb.jpg.9b449cc1858166c2227d35147934c3cf.jpg

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