The Color Correction Tools by Sebastian Goetsch (SG_CCTools) is the first color management system that has been developed ever within any 3D commercial software. Sebastian Goetsch has solved brilliantly a system that not only implements color management facilities within Lightwave 3D, but also facilitates a lot the Classic Linear Workflow. These tools work nicely also with the Inverse Linear Workflow and Multipas Linear Workflow.
Note: I strongly recommend you get an Issue# 18 of HDRI3D magazine where I propose the 3 Linear Workflows mentioned before.
Unzip the files (32Bits version or 64Bits version) in its respective folder. Better if we create a special folder for these plugins - later we’ll see why. Add the 3 plugins in Lightwave.
SG_CCTools is composed by 3 modules:
To replace the Default Picker, go to Options => Preferences => General tab and choose SG_CCPicker as your new Color Picker. Once you have made this, you’ll never come back
The SG_CCPicker is currently the only customizable picker that automatically linearize any color we choose. It has 4 panels:
WinPicker/History Panel - Here we have two ways to pick a color. By using the classic Windows color picker, or by clicking in any place of our screen by using the Screen button. This works if your color source is an image in other window, or if it’s even in another application; we can switch to other program, open any image and choose any color displayed in our screen. This panel stores also the last 30 colors we have used, so this could be an additional way to choose a color.
Tint/Shade Panel - You should already know this useful way to choose colors.
Numerical Panel - We can specify colors directly in XYZ color model. By multiplying values, we can go beyond the 8-bits limit. So yes, SG_CCPicker is floating point (FP) as well.
Config Panel - Here is where reside some of the most powerful features of this picker. There’s possible to customize up to 8 images for our color screen. This means that we can use ANY color wheel or color table (Discreet color wheels, Color Finesse hue offset wheel, Kelvin temperature bar, wavelength bar, HSV>RGB table) or any other color scheme you want to design. We can even get a CMYK Pantone within Lightwave. We can get them all within SG_CCPicker. These color tables can be saved as images of 128x384 pixels.
The Config Panel also allow us to linearize or color encode any color we pick. This color conversions can be made by input any simple gamma curve or more complex gamma formulas for sRGB and Rec. 709.
CMYK color (RGB equivalent) linearized by SG_Picker
Blackbody Temperature / Kelvin
Bluish color, linearized for sRGB, AdobeRGB 1998 and rec. 709
Sebastian’s Tip: Roll your mouse wheel (MW) to increase or decrease saturation. To increase or decrease the brightnes, press RMB + MW. We can see how numbers change in the Numerical tab. Pretty cool eh?
This node was made for cases in which we need to linearize dark 8-bits images. For avoiding quantitizations, it’s beter to perform linearizations on FP space. So for those cases, we may use the blank image trick or solve the task in the nodal system with this tool. Good thing about SG_CCNode (besides it’s pretty fast), is its gamma correction options for simple gamma exponents, sRGB and rec 709.
HD footage linearized with SG_CCNode
For advanced conversions at gamut level, we have the SG_CCFilter. This filter can be used as pre-processing or post-processing depending on the color management workflow we are using.
Note: I strongly recommend you get an Issue# 18 of HDRI3D magazine where I propose a general Color Management Workflow with which the SG_CCTools fits perfectly.
The SG_CCFilter is capable to manage the most advanced color conversions and rendering intends: Perceptual, Absolute Colorimetric, Relative Colorimetric and Saturation.
It uses ICM/ICC color profiles to make this conversions. In order the SG_CCFilter can recognize our color profiles, we need to specify the route in a .txt file. Something like:
…and so on.
This file should be in the same folder where you installed these plugins - that’s why is advisable to create an special folder for the SG_CCTools.
For color profiles, we can use different files from different folders, but in an studio environment or colaborative projects, it’s advisable to keep the same route, in the same order, with the same color profiles for all computer nodes, so that scenes can be portable from computer to computer. It’s also advisable to create folders for both, linear and log versions of these color profiles.
Note: Be sure to separate linear versions from log versions in a different folder from Adobe’s applications, so these applications don’t confuse them if these color profiles share the same internal name.
Since we can perform color conversion with SG_CCFilter, it’s possible also to use it for working accurately in linear light as well. That is to say, for linearizing images taking into account gamut conversions (chromaticities). In order to do this, we need the usual color profile (a gamma encoded version), and a linear version of the same color profile. Since most of the professional color profile makers are not so cheap to only use them for making linear versions of our color profiles and, since color profiles are in dependence of the particular images devices we are using in a given production (film stocks, digital video and photographic cameras, TV systems, scanners, monitors, papers…), I’ll show you how to make a linear color profile in a very cheaper and easy way:
Go here and download ProfileInspector.
Once installed, open the application, go to Browser and load an ICM or ICC color profile. Let’s say AdobeRGB 1998.icm profile. There, we can see the profile structure and some other useful info. What we care now is the signatures in the Tag Table (12 tags). Select the fourth, fifth or sixth tag (rTRC or gTRC, or bTRC) and double click in one of them. We can see the specific gamma curve for this color space in that specific channel (a simple curve exponent in this case). To set a linear gamma, export the curve tag. Name the txt file as aRGB_gamma.txt and save it in your linear profiles folder. Leave the ProfileInspector opened for a moment and open the txt file. We have now the right syntax to change this gamma. Change 2.200000 by 1.000000 and save it again. Come back to ProfileInspector, select rTRC signature and import the new curve you have just saved. Gamma curve should be linear now. Do the same thing with gTRC and bTRC and save this profile as Linear_AdobeRGB 1998 .icm. You have now a linear version of this working color space. We can do this for other color spaces like ProPhotoRGB (very advisable), sRGB, HDTV, or any other color space if you know its gamma formula. Just notice that internally, both profiles (the log version and the linear version) share the same name. Professional Profile makers allow to change this…