Digital Light & Color

Recently, having helped a fellow PWP user and followed with interest the "Colour Balance" (http://www.dl-c.com/board/viewtopic.php?f=4&t=386) message board thread...

...I thought the experimentation and "exploring the possibilities" illustrated here: http://www.ncplus.net/~birchbay/tutoria ... /index.htm may be of interest.

Please note the Preface comments... this usage of the PWP5 Color Balance transform is not generic but specific to a set of images that have multiple RGB Luminance tones that can easily be selected to be neutralized and the main image areas are initially dark because of minor image areas that consist of the trophy reflections.

[Thank you DougH for the permission to illustrate using your DSC_0004.NEF & DSC_0060.NEF image files].

Thanks, Den, for another example of the subtle use of PWP's tools. I was a bit taken aback to see so many pairs in your shot of the Color Balance Transform and had to hit F1 for into. Maybe I once new this, but I doubt it.
Faced with the initial image I might have masked the highlights as you did but then merely used the Brightness Curve. Have I missed the finer points of your approach?

Mike.

MikeG....

(1) JSach's white paper "Color Balance.pdf" discusses PWP5's Color Balance transform in more detail then the "F1" help. The pdf file can be downloaded from here: http://dl-c.com/content/view/34/55/ or linked from the White Paper tab of the electronic manual if it is already in the "Program Files/Digital Light & Color/Picture Window Pro 5/Docs" folder as "Color Balance.pdf".

(2) Approach Finer Points? -- there really are none. This image set provided the opprotunity to easily choose both RGB Luminance tones and 'color casts' to be neutralized [the shadowed white shirt and the white table cloth shadows] in addition to the Gray card. This is not normally available with more common images as it is difficult to have Remove/Add color pairs at the necessary Luminance tones to act as RGB BrightnessCurve control points in the Color Balance transform.

Normally, I would do as you have suggested... use the RGB BrightnessCurve transform with an 'upper' Highlights mask to adjust tone/colors [... or HSV/HSL ColorCurves transform with prefence HSV-V,S or HSL-L,S curves and a Highlight protection mask]... then adjust for white/black point and mid-tone color cast removal with the Color Balance transform using the 3 indicated Remove/Add color pair locations...

The reason being that these two transforms are designed and perhaps better understood if applied separately rather than combined as I have shown. I was just intriqued that under the right circumstances how everything [brightness/contrast/colors/color balance, all with a mask] could be combined into a single transform...

...perhaps even becoming a RAW Dialogue RGB curve edit option, complimenting the existing HSV/HSL slider edit functions.

Thanks for the further explanation.
I have, some time ago, downloaded and printed out, AND put in a ring folder, all the white papers. Clearly it's well past time for some re-reading.

From time to time I need to tidy up scans of old documents - usually associated with my sister's keen interest in genealogy - and I've got into the habit of using the color remap transform in the early stages of such a 'tidy up' This morning, as as exercise and reinforcement of my reading of your color balance demo I used that technique. Rather a low level application I know, but equally effective and quicker than color remap. A more appropriate tool for the job, I suppose. Simpler - without the same subtleties available in the color remap transform.

Now I have to try to remember the technique - or at least that it exists!

Mike.