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View Full Version here: : Cent-A, NGC 5128 Radio Galaxy


Garyh
18-02-2008, 09:49 AM
Hi Folks again..:)
Well last friday night was a beauty as it cleared up just before moonset and stayed clear for many hours before low cloud started to roll in on twilight. Seeing was a but unsteady but that wasn`t going to stop me as clear nights are very rare up here lately!
I just concentrated on one target and this is it. NGC 5128. I have never got a very nice image of this so I am quiet happy with the result. My guiding seemed a bit off but maybe thats the seeing affecting PHD? with slightly oval stars.

Ok image is 14 x 7 min at iso 400 (I am starting to like 400!) with 6" f/5.6 newt and Canon 300D. Guided with Toucam and PHD. Stacked in DSS then finished of in PS. Also had my homemade peltier cooler attached to my camera too keep that noise at bay!
Anyways I am open to all comments.. :)
cheers Gary

iceman
18-02-2008, 09:53 AM
Absolutely stunning!

Beautiful result, Gary. Everything seems to be working very well at the moment.

allan gould
18-02-2008, 10:25 AM
You obviously mean NGC5128. Great photo anyway

Garyh
18-02-2008, 12:04 PM
Thanks Mike! :thumbsup:



LOL thanks Allan, don`t know why I did that shall fix it now!
cheers Gary

EzyStyles
18-02-2008, 12:17 PM
BEAUTIFUL GARY! i love it. colours look spot on and the image looks really smooth.

Ric
18-02-2008, 12:23 PM
Lovely image Gary, everything looks spot on with this one.

It seems to me that the dark dust lane can almost be seen to do a full 360 degrees. I've never noticed that before.

Cheers

marc4darkskies
18-02-2008, 12:59 PM
Really nice image Gary! Good definition and colour in the dust lane. :thumbsup:

I notice a bit of a greenish tint in the halo though and some green stars - perhaps a bit of selective colour balancing would help?

Cheers, Marcus

h0ughy
18-02-2008, 02:28 PM
WOW that is fantastic, absolutely stunning:eyepop:, definitely a benchmark for me to aim for next year when I am fully set up:thumbsup:. So with the accolades out of the way:help::whistle:, what are the coloured doughnuts coming out from the galaxy? its like a yellow white then to a olive/brown/ purple then back to a bluey purple shell? or is that just my monitor?:shrug:

theodog
18-02-2008, 05:54 PM
Nice image Gary.
I too get the colour shift, but I didn't notice it untill it was pointed out.
Still, well done, -stunning image.

Alchemy
18-02-2008, 07:24 PM
Heres a method to tighten up your stars
copy and paste layer over original (use full size image for this),
select v to move,
using arrows move up and accross one or two pixels.
change blending mode to darken and stars will become more round.

if you are being more accurate you can resize to 300 % do this then resize down.

it may or may not improve the image as a whole, you can also do this selectively to areas if it affects the galaxy too much and that way minimise any unwanted effects. Worth a try anyway.

Garyh
19-02-2008, 01:53 PM
Thanks Eric! it was a cooler night which helped alot with the noise...:thumbsup:



Thanks Ric, always a pleasure! :)



Thanks Marcus! yeah I did play with the color balance a bit and I think I mucked it up a bit..back to have another go at it!
cheers Gary



Thanks houghy for pointing that out...
I didn`t really notice them till you pointed them out. I did notice the outer zone being a bit bluish but trying to color balance the galaxy I stuffed it up a bit..Have reprocessed it again and attached...:thumbsup:



Thanks Jeff, I am happy with it except what has been noticed by a few of you...which is great! One has to get these colors right...:thumbsup:



Thanks Alchemy for that tip!..:thumbsup: I shall give it a go later!
Always good to learn a good tip..:)

Thanks guys,
I have done a second go at stacking and processing this and have attached below..I think its much improved!...:thumbsup:

I seem to get that banding or zoning when I use iso 400? Not sure why that is but...maybe its the dynamic range at that iso. Don`t really see it at iso 800. When stretching the image it just maked them more pronounced..:shrug: any ideas?
cheers Gary

Alchemy
19-02-2008, 06:36 PM
if you did youre processing in the jpg format you might get this, check the histogram of the finished image , does it have gaps or is it smooth?
i proccess in 16 bit TIFF ..... thats the first thing that comes to mind, as it suggests missing tonal range providing a discreet "step"

i cant see why 400 would be different providing you have got solid data to start with.

Geoff45
19-02-2008, 09:25 PM
Actually the best way to do this is to select just the stars and put them in a separate layer and then do the above process. This avoids messing up the galaxy image. Star selection is dealt with in Ron Wodaski's book the Zone System and is quite easy to do, but would take too long to explain here.

Great image!
Geoff

Peter Ward
19-02-2008, 09:33 PM
That's a great image Gary.:thumbsup:

You might need to tighten up the focus & guiding just a tad, but, hey you knew that already.

Colour, dynamic range, processing all good. Stick with it!

Peter

Tamtarn
19-02-2008, 11:40 PM
The reprocessed image is terrific Gary. Very smooth background and nice colour balance. Very nice.

theodog
20-02-2008, 06:26 AM
Well done Gary.
Makes a good image even better.:)

marc4darkskies
20-02-2008, 08:36 AM
Ah ha! Much better now Gary - colours look right! Good job! :thumbsup:

Cheers, Marcus

iceman
20-02-2008, 08:46 AM
Incredible image, Gary. Repro is great.

Garyh
20-02-2008, 08:11 PM
Thanks Alchemy, Geoff (will try that!), Peter, Barb and Dave, Jeff, Marcus and Mike for the extra feedback! :thumbsup:
It really helps to improve on ones skills with processing which is a never ending learning curve..
Thanks everyone.. :)