Yeahh Matt Ebb just commit my patch (SVN r27733) for the “Color Balance” node in Blender 2.5 Compositing node !!! Now it should be much easier to work with.
You can get a version of blender at Graphicall.org (any version above revision 27733)
There is still some precision issue on the color wheels, I guess some day it will be possible to move the color picker slower.
How to use it ?
First I would recommend you to un-check the “color management” setting in Blender 2.5 or it will make the blacks really hard to control.
If you are not so familiar with color grading, and push-pull techniques, I would really recommend you to watch Stu Maschwitz’s (Prolost) video tutorial using Magic Bullet Colorista. The settings won’t be exactly the same, but the approach quite the same though !
I described the Lift/Gamma/Gain in a previous post, and mostly this node is based on the formulas specified there. We just slightly modified it so the 3 defaults values parameters are equal to 1.0 just like in Colorista. Which makes it much easier to control the blacks. Actually the “Color Balance” node before this revision was the same formula but with lift default value equal to 0.0
Some presets !
While making some comparison test between Colorista in After Fx and the “color balance” node in blender, I tried to mimic some of Colorista’s presets.
You can download the “Blender Color Grading Presets” here : http://code.google.com/p/ft-projects/downloads/list
Since there is no mask in the “Compositing Editor” of Blender yet, I found a simple tricks which could work pretty well especially in case of color grading.
You’ll see nothing really fancy here since the mask can only be square (or pretty close to a square shape though). But if you check out Colorista for instance, the two allowed shapes are ellipse and rectangle.
I got lately interest in Lift/Gamma/Gain formula for some personal project, I thought I would share some of the informations I found.
What does Lift/Gamma/Gain ?
Lift/Gamma/Gain is actually is a really nice approach for color correction in my opinion. Lift/Gamma/Gain are actually controlling the Shadows/Mid-tones/High-tones of your picture with the ability to offset the colors.
This combine with saturation and exposure could give a powerful tool for color correction. This is the kind of tool you’ll find in plug-in such as Magic Bullet Colorista from Red Giant Software or professional hardware as Black Magic DaVinci
This has to be done for each channel color for each pixels of your picture.
To make some test of this formula I did use Blender’s compositing and its “Math” node which was pretty useful 🙂 . This operation is useless since it is terribly slow using nodes and it’s already implemented in the Sequencer (properties of the strip), but it’s just for the test !