Luminous Landscape Forum

Raw & Post Processing, Printing => Colour Management => Topic started by: Guillermo Luijk on November 03, 2016, 01:33:12 pm

Title: HELP: simple software to project image colours over the CIE 1931 diagram
Post by: Guillermo Luijk on November 03, 2016, 01:33:12 pm

I cannot fin a simple piece of free software that can do this. Do any in the forum know of a piece of software to achieve this? (Windows OS)

Image bottom right is what I'm looking for:

(http://colour-science.org/images/Colour_-_Analysis_CIE_xyY.gif)

Thanks!

Title: Re: HELP: simple software to project image colours over the CIE 1931 diagram
Post by: Mark D Segal on November 03, 2016, 05:10:27 pm

Not sure whether it will do exactly this, but have you looked at Chromix ColorThink Pro?

Title: Re: HELP: simple software to project image colours over the CIE 1931 diagram
Post by: TonyW on November 03, 2016, 06:52:45 pm

The only one I know of is as Mark mentioned Color Think Pro (it will plot image data points within CIE diagram) - but it is pretty expensive

While I do not think it will be exactly what you are looking for I wonder if 3D Color Inspector plugin for ImageJ (with a little compositing in PS  ;)) would be helpful ?

Screen grab
(http://i298.photobucket.com/albums/mm256/TonyWarrington/ColourInspector.jpg) (http://s298.photobucket.com/user/TonyWarrington/media/ColourInspector.jpg.html)

Links
https://imagej.nih.gov/ij/
https://imagej.nih.gov/ij/plugins/color-inspector.html

Title: Re: HELP: simple software to project image colours over the CIE 1931 diagram
Post by: TRANTOR on November 03, 2016, 07:00:37 pm

3D plot within Lab: http://www.colorlab.no/colourlab_old/icc3d
Free of course.

Title: Re: HELP: simple software to project image colours over the CIE 1931 diagram
Post by: Guillermo Luijk on December 07, 2016, 01:53:30 pm

Thank you all. The tool referenced by Tony was fine.

This was a case of study of stage led lights, some forum members indicated overexposure as the problem in this shot:

(http://www.guillermoluijk.com/article/ledlight/reveladoinicialacr_lite.png) (http://www.guillermoluijk.com/article/ledlight/reveladoinicialacr.png)


But the RAW exposure was perfect (only quasi specular lights got clipped):

RAW histogram:
(http://www.guillermoluijk.com/article/ledlight/histraw1.png)

Zooming the highlights to find the dancer:
(http://www.guillermoluijk.com/article/ledlight/histraw2.png)

RAW clipped areas:
(http://www.guillermoluijk.com/article/ledlight/bayer1.png)

Zooming:
(http://www.guillermoluijk.com/article/ledlight/bayer2.png)

RAW red channel, the most exposed:
(http://www.guillermoluijk.com/article/ledlight/bayer3.png)

Conclusion: exposure was perfect.

What was the problem then? these artificial colours are so saturared that sRGB is in sufficient even for a neutral RAW development, ProPhoto RGB does the job:
(http://www.guillermoluijk.com/article/ledlight/prophotorgb.png)

Displaying colours out of sRGB:
(http://www.guillermoluijk.com/article/ledlight/gamut1.png)

3D vision:
(http://www.guillermoluijk.com/article/ledlight/gamut2.png)

Regards!

www.guillermoluijk.com