Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: The Thing on Apr 14, 2019, 11:43:27

Title: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: The Thing on Apr 14, 2019, 11:43:27
I've tried out a procedure for separating the stars and DSOs in StarTools, which worked OK but has left me with glowing halos around the galaxies. The upside is they are far easier to pick out! I toned down the star colour to try and show up the galaxies more. This would be a good target for the BananaScope as the superior optics will show more than my little newt.

30x250s Gain121 Offset 4 T-15c Captured with NINA
Processed in PixInsight, StarTools, IrfanView

Image date, time and location:   2019-04-12 03:30CET Manche, France
Telescope aperture and focal ratio:   TS1506UNC f4, TS Komakorr
Camera and filters used:   ZWO ASI294MC Pro, Baader Neodymnium 1.25" filter
Processing applied:   Pixinsight, StarTools, Irfanview

Click for full size, uncropped, unbinned.
(http://gallery.orpington-astronomy.org.uk/albums/userpics/10050/normal_Hercules_Galaxy_Cluster_30x250s_G121_O4_T-15_NINA_PI_ST_IV.jpg) (http://gallery.orpington-astronomy.org.uk/albums/userpics/10050/Hercules_Galaxy_Cluster_30x250s_G121_O4_T-15_NINA_PI_ST_IV.jpg)


Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: JohnP on Apr 14, 2019, 14:59:45
umm looks like a promising image but weird processing - the procedure of separating stars & DSo's has definitely not worked also background looks too black. Did you try the procedure you used for processing your previous star cluster on this as the results you got for that were superb.  john
Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: MarkS on Apr 14, 2019, 15:12:27
I agree with John.  The processing has caused some weird artifacts and the background is clipped to black.

However, it looks like a very interesting area for imaging!

Mark
Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: NoelC on Apr 15, 2019, 18:40:55
The galaxy shapes are quite distinct; if you can sort out the halos it'll be a terrific image. 
Either that or we just need to top up with a bit more anti-freeze and the general haze should cancel it out.
Very interesting subject.

Noel
Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: The Thing on Apr 15, 2019, 20:44:12
Thanks Noel, I've been cogitating and think it was the StarTools Life module which tries to add 'life' to dull DSO images, I'll redo the processing and leave it out.
Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: Fay on Apr 15, 2019, 22:02:18
I also love the area, all those galaxies in one area
Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: Carole on Apr 16, 2019, 20:45:58
My word, there are loads of them.  Have you tried counting them?

Carole
Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: The Thing on Apr 16, 2019, 21:52:40
It's pretty amazing, a target I stumbled across a couple of months ago. I'm going to have another go when the next New Moon comes along. Of course tonight the sky is completely clear but the Moon is a floodlight above me so completely unsuitable for hundreds of faint galaxies.

I have just cleaned the mirror and recollimated so I want to test my efforts which is why I'm down the garden. Looking very good so far. But the cable for the focuser motor is bust. Win some lose some.
Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: RobertM on Apr 17, 2019, 21:36:21
Hi Duncan,

I agree with john, the background is black and that's produced the haloes around all those nice little galaxies.  Other than that a very nice result.

Wish I had dark skies like that :cry:

Robert
Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: The Thing on Apr 18, 2019, 16:37:29
Thanks Robert, I put a bit too much contrast into the extracted stars image and so blackened the background too much, and the Star Tools life module enhanced the galaxy halos on the other half of the image so a double whammy. But at least I learnt how to do the separation - much easier than PI.

Quote from: RobertM on Apr 17, 2019, 21:36:21
Wish I had dark skies like that :cry:

Robert

That makes me think of you that time you visited (2014!). We were hoping for a break in the clouds as the dew made every thing soaking wet! You saw how dark the skies are for only 30 mins or so :( It's much more civilised here now, no mud, puddles and builders stuff to trip over in the dark :)

Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: RobertM on Apr 19, 2019, 12:59:54
That should be called the Life and Death module !   I would agree Startools is much simpler (in theory) but one of the PI strengths (and weaknesses is the fine degree of control.  I remember ST went quiet a while back; has the developer started working on  it again ?

Robert
Title: Re: Hercules Galaxy Cluster - Abell 2151, 2019-04-12 03:30CET Manche, France
Post by: The Thing on Apr 19, 2019, 13:42:26
Yes, the developer did some fixes and tweaks - he claims it is finished so hes not working on it except when necessary. I think the issue with ST is you need to think differently to using 'standard' methods of post-processing, for instance separating the stars and galaxies using a module called Heal to blot out the stars is not obvious!