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Hoshino: Case Study
July 4, 2017 11:38 am Leave a Comment

Our contribution to the recent Star Wars Fan Film: Hoshino (not affiliated with LucasFilm or Disney) involved helping design the overall look, integrating the visual effects, and performing the final color grading.
We worked alongside director Stephen Vitale and cinematographers Ryan Broomberg and Alyssa Brocato to achieve the final result.
Color Workflow
Since the project pays homage to the original Star Wars trilogy, we decided to follow a traditional film post-production workflow, while still shooting on a digital format.
Part of this process involved creating a Custom LUT for the production camera (RED Epic Dragon) which transformed the color to have a more organic feel. This was an early incarnation of our FilmMatrix LUT (part of the RED to Alexa LUT Package).
A customized Print Film Emulation LUT was also used at the end of the grade. This prevented saturated colors from becoming too bright and made the digital image behave more like film.
VFX Integration
When creating photo-realistic composites, it’s generally best to work with the camera’s raw scene-linear data (before any non-linear / destructive grading occurs). However, some elements (like lightsabers) need to be placed after the grade in order to maintain consistent colors throughout the film. Therefore, the visual effects were divided into two categories: Pre-Grade and Post-Grade.
Pre-Grade VFX
This category included things like adding CG elements, keying green-screen shots, and painting out objects.
To aid with integration, separate preview LUTs were also generated for each effect shot. This allowed for the VFX to be seen with the grade applied (before any rendering occurred), and the shots could be fine-tuned accordingly.
Post-Grade VFX
Other effects such as lightsabers, lasers, and text overlays were applied after the grade (though still before the Print Film Emulation LUT).
In some cases, if a shot had both pre-grade and post-grade VFX, we implemented the final grade as a LUT inside the effects pipeline – reducing the amount of rendering and storage space required.
Attention was made to ensure the LUTs didn’t cause any banding or color artifacts. Learn more about Stress-Testing LUTs.
Behind the Scenes
Check out the making-of featurette:

Contact
For more information, please visit our services page. Or feel free to contact us with any post-production inquiries.
RED to Alexa LUT Package
January 1, 2017 2:27 pm Leave a Comment

This package transforms RED material to closely emulate an ARRI Alexa’s gamma and colorspace – providing an alternative starting point for further grading.
The LUTs are based on an average of actual camera data. Additional grading may still be required to completely match the two cameras in a particular scene. Try out the Interactive Demo.
*Works with all RED camera models & sensors.
Quality
Built with precision and quality control, the LUTs have been thoroughly stress tested and do not introduce any unwanted banding or color artifacts.
Gamma
The Log3G10 gamma curve is mathematically transformed to ARRI’s LogC format. Some highlight rolloff was added to avoid clipping luminance data. This serves as the base for all other colorspace conversions.
Colorspace
The color information is transformed from REDWideGamutRGB to a variety of ARRI formats using our Camera Profiling process. Since REDWideGamutRGB is a standardized colorspace, this LUT package works across all RED camera models.
All the LUTs implement a tone-mapping process to retain out-of-gamut colors.
ARRI WideGamut
This is the foundation for all other colorspace transforms. The wide gamut colorspace provides the most room for color grading and image manipulation. This is usually combined with ARRI’s standard LogC2Rec709 transform.
ARRI FilmMatrix
An option using ARRI’s Film Matrix is included as well. This was originally built for the Alexa to mimic the color characteristics of film from an ARRI scanner. Ideal for a traditional film workflow involving a separate Print Film Emulation LUT.
AlexaV3Rec709
Intended for dailies and in-camera previewing, the LUT is based on combining our “ARRIWideGamut” LUT with the ARRI LUT Generator’s standard LogC to Rec709 transform curve, but has been re-built to better roll-off the saturation on RED footage.
ALEXA LOOK
This transform is for use as a “Creative 3D LUT” in conjunction with RED’s new IPP2 system. When used with our recommended settings, the result is designed to look similar to our “AlexaV3Rec709” LUT.
IPP2 settings: Medium Contrast / Soft Rolloff.
Post Workflow
Based on a traditional log workflow, grading should be applied after the TRUECOLOR LUT, but before the output Display LUT.
Also watch some of the recommended workflows using RED Cine-X and DaVinci Resolve:

Examples
The following video shows how our LUT compares to an actual ARRI Alexa under various lighting conditions. RED’s default IPP2 settings are also shown for reference (Medium Contrast & Medium Rolloff).
Our goal was to match each shot as closely as possible by only adjusting the White Balance, Tint, and Exposure settings. Better results could be obtained through the use of secondary color corrections.
More details about the camera settings are available in the PDF.

Download
You can purchase the LUT package here: https://truecolor.us/downloads/red-to-alexa-lut-package
For any other inquiries about the LUT, please contact us.
Not All LUTs Are Created Equal
December 24, 2016 9:59 pm Leave a Comment

Today there are many stylized “look LUTs” available, designed to make your footage appear more cinematic. But what are these LUTs really doing under the hood?
Analysis
When analyzed against a stress-test image, many of these LUTs exhibit severe banding and color artifacts – negatively affecting the image quality.
The following image has a generic film display LUT applied. On the surface, everything may appear normal:
However, increasing the viewing gamma to 4.0 reveals some problematic areas hiding in the shadows:
In a different example of a LUT implementing a “film look”, isolating the individual red, green, and blue channels shows the unevenness in saturated areas:
While the LUT may appear to work on some shots, inevitably these kinds of LUTs will encounter an image that “breaks” them and sometimes no amount of creative grading can fix the problem. The solution lies in the overall LUT construction.
Quality LUTs
Some may be tempted to abandon LUTs altogether, however LUTs provide the ability to non-linearly adjust color. This is ideal for remapping out-of-gamut colors or when mimicking the characteristics of film.
The real issue comes down to quality, and as the title of this article states: not all LUTs are created equal.
A good LUT doesn’t introduce any artifacts of its own – it cleanly transforms the input color to the output color.
If the source footage contains banding, obviously the LUT can’t improve that (garbage in, garbage out). However, when applied to a high bit-depth image with the expected input parameters, a well-made LUT can work beautifully.
One example of a high-quality look-up table is our free REDcolor4 LUT, which was built to avoid the issues shown above:
When considering using a LUT for a project, it’s a good idea to thoroughly stress-test it beforehand, rather than find out later it’s causing unfixable artifacts.
Download
You can download the free LUT Stress Test Image here:
https://truecolor.us/downloads/lut-stress-test-image
To use the stress test image: first apply a LUT, then see how it behaves when increasing/decreasing the gamma (applied after the LUT). Also, try viewing the individual red, green, and blue color channels as well.
LUT Stress Test Image
8:55 pm Comments Off on LUT Stress Test Image
Not all LUTs are created equal. This image helps identify potential problems and artifacts with look-up tables… Learn More
1.01 Update – 08/22/2018
- Refined the overall layout
REDcolor4 LUT
November 5, 2016 5:41 pm Leave a Comment

REDWideGamutRGB is the new standardized 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 Rec709 monitor.
Our LUT converts REDWideGamutRGB to REDcolor4 using additional saturation mapping 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.
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:
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:
Using REDWideGamutRGB combined with our REDcolor4 LUT, gamut mapping can be controlled while still achieving a decent level of saturation:
The differences can also be seen on a color chart:
The LUT does not merely increase saturation but instead matches REDWideGamutRGB to REDcolor4 – allowing for more consistency when intercutting footage using both colorspace settings. Learn more about the Camera Profiling process.
Download
You can download the free REDcolor4 LUT here:
www.truecolor.us/downloads/redcolor4-lut/
To work as intended, the source material needs to be set to REDWideGamutRGB / REDlogFilm. The suggested workflow is as follows:
If you have any feedback regarding the LUT, please let us know.
REDcolor4 LUT
5:25 pm Leave a Comment
The LUT transforms REDWideGamutRGB to REDcolor4 using additional saturation mapping for out-of-gamut colors… Learn More
Included LUT Formats:
Iridas x64 .cube
Iridas x32 .cube
Autodesk x17 12bit .3dl
1.01 Update – 08/22/2018
Rebuilt the LUT with an improved REDcolor4 algorithm