Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: RobertM on Oct 18, 2013, 22:00:31

Title: M31 Luminance two panel mosaic
Post by: RobertM on Oct 18, 2013, 22:00:31
After all the pain with the Iris, this is just a simple process.  Dynamic background extraction for flats, dark structure enhancement and HDR range compression.  Don't have your monitor turned up too bright ! I will redo soon - and yes this too needs RGB :(

Top panel: 14 x 600s
Bottom panel: 12 x 600s

Borg 77EDII@f/4.3
Starlight-Xpress SXVR-H694
Luminance filter

(http://farm8.staticflickr.com/7317/10351339815_c12ce9b3dc_b.jpg)

Warty size: http://farm8.staticflickr.com/7317/10351339815_3bcc93e18f_o.jpg (http://farm8.staticflickr.com/7317/10351339815_3bcc93e18f_o.jpg)

TFL
Robert
Title: Re: M31 Luminance two panel mosaic
Post by: JohnP on Oct 18, 2013, 22:07:55
Very nice again Robert & I can't even see the join ;-) Amazing looks like you can see dust lanes in one of the two companion galaxies (can't remember what number it is but the top one of the two in your image). Also some other background fuzzies to spot.

Nice one,  John
Title: Re: M31 Luminance two panel mosaic
Post by: Rocket Pooch on Oct 19, 2013, 08:48:37
Oh thats what you were up to...
Title: Re: M31 Luminance two panel mosaic
Post by: The Thing on Oct 19, 2013, 12:10:16
That's got so much detail Robert. There's a few faint fuzzies lurking as well.
Title: Re: M31 Luminance two panel mosaic
Post by: MarkS on Oct 19, 2013, 12:26:18
Very nice - you've got some good data there.

You're going to have with the gradients along the join!
Title: Re: M31 Luminance two panel mosaic
Post by: Fay on Oct 19, 2013, 14:00:10
i knew it would come out well Robert!
Title: Re: M31 Luminance two panel mosaic
Post by: julian on Oct 19, 2013, 15:45:54
Nice one Robert
Title: Re: M31 Luminance two panel mosaic
Post by: RobertM on Oct 20, 2013, 19:15:28
Quote from: MarkS on Oct 19, 2013, 12:26:18
Very nice - you've got some good data there.

You're going to have with the gradients along the join!

Yes I know, I didn't apply the background extraction properly but I'll get it right in the real version.
Title: Re: M31 Luminance two panel mosaic
Post by: RobertM on Oct 21, 2013, 23:35:10
This is more or less there, I could do some range compression to show the core more plus some sharpening - what do you think ?

(http://farm6.staticflickr.com/5545/10411628363_d30afc1b72_b.jpg)

Full size (fewer warts this time): http://farm6.staticflickr.com/5545/10411628363_508ee424ab_o.jpg (http://farm6.staticflickr.com/5545/10411628363_508ee424ab_o.jpg)

If you look close enough you will see a join but it's quite subdued even on the full size version.

Now I need to capture colour data for the other pane (yes I have only one) ...

Robert
Title: Re: M31 Luminance two panel mosaic
Post by: MarkS on Oct 22, 2013, 00:30:45

I can't see the join this time!

However, I prefer the appearance of the stars in the original image - they appeared a lot tighter.  In the latest version they have become a lot more blobby and measles-like for some reason.

Mark
Title: Re: M31 Luminance two panel mosaic
Post by: JohnP on Oct 22, 2013, 07:48:38
First has a more 'milky' appearance - i.e. background nebulosity. Second is more contrasty but like Mark says stars are larger.. either way still a fantastic image - Like I said in my original comment I dont think I have ever seen lane structure in m110 before... fantastic.
Title: Re: M31 Luminance two panel mosaic
Post by: RobertM on Oct 22, 2013, 09:26:56
Thanks for the comments, much appreciated.  I see what you mean about the stars, that could be due to the range compression I used in the first.  Admittedly I did use entirely different processing techniques for each so some difference is to be expected.  I'll also set the black point a bit lower to bring in the background a bit more.

Robert