Centaurus A now over 15 hours repro

[gregbradley]

I added about 4:30 hours of 12.5 RCOS and STL11 data I had to the 10:40 I had using a TEC180.

The result is here:

http://upload.pbase.com/gregbradley/image/125007732/large

I have highlighted the blue "jet" area. It seems to me to be the wrap around of the original spiral galaxy and a star forming area. That is how it appears anyway.

Greg.

[jase]

Crunchy and bold processing Greg. You've achieved your goal of highlighting the blue stream alas this has come at a price. Black clipped in all channels - never a good thing. You need to take more care with your data and spend additional time working it over. We're talking fundamentals here. Time for a repro.

Apologies if I sound harsh, but given the gear you're using, I'd certainly be expecting more.

[iceman]

There's definitely something not right with the processing, Greg. Have you changed monitors? It's not like your usual work.

[multiweb]

Yep - this one (http://www.buytelescopes.com/PostComments.aspx?id=39037) looked much smoother.

[DavidTrap]

Agreed. (Still impressive though.)

DT

[gregbradley]

Fair enough. I'll delete it for now pending a repro if it can be done. The 2 sets of images were at different orientations so there was a lot of cropping.

It may be easier to take new hours.

Greg.

[gregbradley]

OK, repro done. Did the final colour on my regular computer monitor and it also gave a different shade on colour. I had callibrated this one using the Adobe callibration routine that comes with Photoshop.

Anyway, redone and corrected.

The blue "jet" is highlighted and seems it may in fact be a wrap around of the original spiral galaxy and possibly a star formation area.

http://www.pbase.com/gregbradley/image/125013790/large

Greg.

[iceman]

Much, much better!!

[CoolhandJo]

Very nice indeed!

[Hagar]

Well done Greg, The second image is a vast improvement.

[multiweb]

Great stuff. :thumbsup::thumbsup::thumbsup:

[gregbradley]

Yes thanks Mike. You were right I need to keep to one computer for the colour processing.



Thanks for that.



Thanks Doug. I need to stick to one computer to do the processing. Different screens have different callibrations in colour. Also black clipped the first one. A corny error.



Thanks Marc.

[DavidU]

That's it ! Fabulous.

[RB]

Greg that's much better compared to the original.
I personally like to have a little bit of a gap on the left of the histogram before it starts to rise, it gives a more natural looking background.

I highly recommend using a dedicated computer with a good monitor that's regularly calibrated.
I have a dual monitor setup, Dell 2408WFP and a Dell 2209WA and use the Spyder Pro to calibrate them regularly.

I make sure I have the same colourspace running and have "Proof Colours" ticked under the "View" menu in Photoshop, (thanks for the tip Jase). :P

Anyway mate glad to see the repro.

Cheers
Andrew

[gregbradley]

Thanks David.



Good tips Andrew. I may need to get a separate monitor that is callibrated like you mention. Its vital for image processing that you get an accurate view of your image otherwise you are running blind.

Greg

[marc4darkskies]

You're definitely going deep there Greg and the later version is much nicer - a striking image!

As others have said, unless you're subject is a small galaxy in an otherwise featureless dark field, leave some space at the black end of the histogram and try and give the black end a bit of a tail and some slope (ie not a vertical transition)

And if you don't already have one - get yourself a good 10 or 12 bit monitor!

Cheers, Marcus

[jase]

Much improved Greg. Well done.

[gregbradley]

Yes I think I will. Cheers Marcus.



Thanks Jase.

[Bassnut]

Bright and deep Greg, top work.

[RobF]

Fantastic image - I've never noticed the blue regions before - no doubt as they're so hard to detect and process successfully.

[gregbradley]

Thanks Fred. The big hours are where its at in this game ultimately.



Yes that blue jet is usually a very subtle detail.

Greg.