Another Centaurus A

Greg had recently posted an image of this object and I had just completed the processing on my offering. I have attached a mid size image. Full size and exposure processing details are at:

http://jthommes.com/Astro/NGC5128.htm

Greg commented on how much larger this object is compared to many images you see of it. I got a similar result, but due to those other images, I treated the size in my image as a gradient and removed part of it . Another observation is that I probably imaged closer to the horizion (it maxes out at 12 degrees altitude from my geography). I did not factor for atmospheric extinction so it is a bit "redder" than Greg's.

Attached Image:

Jim Thommes said:
it maxes out at 12 degrees altitude from my geography

Imaging that low shows that you're braver than I, Jim.
I rarely start a series unless it's above 45 degrees.
In any event, it's a remarkable image.
My regards,

dan kowall

Wow Jim you got tons of detail for shooting so low! thats an excellent image, one of the best I've seen from this far north. I think you got the colors nailed also. This appears to have some of the best color balance you have attained in your images. I just cant seem to get colors that accurate, did you do something different in this image?

Vince

Excellent! 8)

Thanks everyone for your comments...

Vince, regarding the color balance, I had recently attended an RTMC presentation on "getting the color right". The presenter emphasized the use of a "G2V" star color calibration. I recently took exposures to calibrate my Edmund Optics RGB Dichroics and I appplied those factors to the color balance. As I mentioned, I had not taken into account atmoshperic extinction. So I worked up some factors for the site elevation (2000 meters in the Lagunas) and my angle from Zenith. I applied those factors to obtain this new image. So the attached image is color calibrated (G2V) and compensated for extinction. You can also get a full size image here (be sure to click th image on the page for full size):

http://jthommes.com/Astro/NGC5128.htm

I personally like the colors better than the original post. I imagine there will be a range of opinions.

Attached Image:

That is a really fine image Jim. You see the spray of blue star forming areas and the band of dust can be seen to go around the other side of the main galaxy (this is 2 galaxies that have collided).

Brilliant, especially seeing as it must be quite low for you.

Imagine what you could have captured here at near the zenith!

Greg.

Hi Jim,

I like both versions! I look forward to seeing your G2V-calibrated colors in the future!

Eric