M81 first image processed with PI (and PS6)

[Robovet]

This image was taken with an Edge HD 11 at F10 with an Apogee U16. L 9 x 10 RGB 10 x 5min 2x2. CCD stack was used to calibrate flats,darks and align. The individual LRGB files were combined, color calibrated and HDRmultiscale applied following the video tutorial of NGC 1808. In addition a deconvoluted version was made. The images were then brought into photoshop for further enhancements. I have always had problems balancing color with photoshop (maybe because i'm colorblind), and PI was much easier for me to make the RGB. I know some of the problems with this image could be solved by calibrating in PI but I'm very used to the workflow in CCDStack.

http://www.flickr.com/photos/94597165@N00/8690568795/in/set-72157627952631911/lightbox/

Criticisms and suggestions welcome--

marc

[Geoff]

Lots of good detail Marc, but the colour is way off.  Did you colour calibrate the RGB file before stretching?  Remember that CC won't work on nonlinear images.

[Robovet]

The color calibration was done before the Histogram transformation on the linear file.

[Robovet]

Geoff,

I'm going to re-process again to fix the color. Is their too much red or just too much saturation overall ? Any guidance would be appreciated.

Marc

[Geoff]

Hi Marc
My first impression was that there was too much magenta, but when I looked at the histogram, all 3 colour peaks lined up, which is what you'd expect from a colour balanced image.  Then I tried a strong reduction of the saturation in Curves.  Much better! I've attached a screen shot.  It could probably still do with a bit less saturation.
Geoff

[Robovet]

Thanks Geoff,

I'm gonna work on it this weekend and re-post the image

marc

[Geoff]

BTW I should mention that reducing the saturation by Curves only gives a pointer to the nature of the problem. You will need to find what caused it in the first place.
Good luck with the repro.

[Robovet]

Hi Geoff,

I re-processed :

http://www.flickr.com/photos/94597165@N00/8706327046/in/set-72157627952631911/

[lucchett]

Hi,
I still see the same issue.
Did you assign a srgb icc profile?
The color is way off and you should notice this.
I wonder if we are looking at the same color...
Andrea

[Robovet]

Yeah I guess its pretty pink. I think I';m just gonna start over with the fits files from scratch to see what went wrong

Thanks--

[Harry page]

Hi

Colour correction works quite well

But you must get most of the galaxy in , inc the faint arms so adjust settings carefully and a bit of scnr to remove some green after cc

Regards

Harry