Centaurus A now over 15 hours repro

gregbradley · #1 29-05-2010, 12:18 PM

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/...25007732/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 (Jason) · #2 29-05-2010, 12:36 PM

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 (Mike) · #3 29-05-2010, 04:32 PM

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

multiweb (Marc) · #4 29-05-2010, 04:37 PM

Yep - this one looked much smoother.

DavidTrap (David) · #5 29-05-2010, 04:43 PM

Agreed. (Still impressive though.)

DT

gregbradley · #6 29-05-2010, 05:29 PM

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 · #7 29-05-2010, 06:24 PM

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 (Mike) · #8 30-05-2010, 05:59 AM

Much, much better!!

CoolhandJo (Paul) · #9 30-05-2010, 08:03 AM

Very nice indeed!

Hagar (Doug) · #10 30-05-2010, 08:59 AM

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

multiweb (Marc) · #11 30-05-2010, 09:40 AM

Quote:

Originally Posted by gregbradley

OK, repro done.

Great stuff.

gregbradley · #12 30-05-2010, 10:27 AM

Quote:

Originally Posted by iceman

Much, much better!!

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

Quote:

Originally Posted by CoolhandJo

Very nice indeed!

Thanks for that.

Quote:

Originally Posted by Hagar

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

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.

Quote:

Originally Posted by multiweb

Great stuff.

Thanks Marc.

DavidU (Dave) · #13 30-05-2010, 10:38 AM

That's it ! Fabulous.

RB (Andrew) · #14 30-05-2010, 11:00 AM

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).

Anyway mate glad to see the repro.

Cheers
Andrew

gregbradley · #15 30-05-2010, 12:21 PM

Quote:

Originally Posted by DavidU

That's it ! Fabulous.

Thanks David.

Quote:

Originally Posted by 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).

Anyway mate glad to see the repro.

Cheers
Andrew

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 (Marcus) · #16 30-05-2010, 01:03 PM

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 (Jason) · #17 30-05-2010, 09:54 PM

Much improved Greg. Well done.

gregbradley · #18 30-05-2010, 11:47 PM

Quote:

Originally Posted by 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

Yes I think I will. Cheers Marcus.

Quote:

Originally Posted by jase

Much improved Greg. Well done.

Thanks Jase.

Bassnut (Fred) · #19 31-05-2010, 06:24 PM

Bright and deep Greg, top work.

RobF (Rob) · #20 31-05-2010, 08:16 PM

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