FREE Saturation Rolloff LUT

REDWideGamutRGB is a new colorspace option for RED footage. It can reproduce a much larger range of colors than REDcolor4, which is very useful for shots that have high saturation levels. However, it will look desaturated on a traditional monitor.

The saturation rolloff LUT matches REDWideGamutRGB to REDcolor4, but with some additional color remapping for out-of-gamut colors.

Background

Currently Rec709 is the colorspace standard for HDTVs and consumer displays. It is depicted as the triangle below, surrounded by all visible colors of light. If a color falls outside of the triangle, it is considered out-of-gamut and cannot be seen on the display.

Rec709 Gamut

Digital cinema cameras (like RED) capture a much wider gamut of color than Rec709 devices can reproduce. In order to view the image properly, some color transformations must take place.

Example

The REDWideGamutRGB colorspace encompasses every color the camera sees, but it appears desaturated on a normal Rec709 device:

REDWideGamutRGB Comparison

REDcolor4 scales up the saturation, but it is unable to reproduce all the colors that were captured by the camera. This eventually can result in clipping image data for out-of-gamut colors:

REDcolor4 Comparison

Using REDWideGamutRGB combined with the saturation rolloff LUT, gamut remapping can be controlled while still achieving a decent level of saturation:

Saturation Rolloff LUT Comparison

The differences can also be seen on a color chart:

REDcolor4 LUT Comparison

The LUT does not merely increase saturation but instead matches REDWideGamutRGB to REDcolor4 – allowing for more consistency when intercutting footage using both colorspaces. Learn more about the Camera Profiling process.

Download

You can download the FREE saturation rolloff LUT here:
http://truecolor.us/downloads/free-saturation-rolloff-lut/

To work as intended, the source material needs to be set to REDWideGamutRGB / REDlogFilm. The suggested workflow is as follows:

LUT Workflow

If you have any feedback regarding the LUT, please let us know.