If you’ve recently entered the world of video creation you might have encountered the term “LUT.”
So, what exactly is a LUT and why does it matter in the world of color correction or grading?
Understanding the Basics
To kick things off let’s start with a straightforward LUT definition: LUT stands for “lookup table.”
Essentially it’s a table of values that dictate how colors in an image should be transformed from the original.
Imagine it as a set of instructions telling the system how to adjust brightness, contrast, and color cast for each specific color value in your footage.
LUTs come in various file formats like .lut and .cube each with its own specifications.
While you can download LUTs from creative websites or manufacturers you can also create them using grading applications like DaVinci Resolve.
LUTs vs. Looks
Before diving deeper it’s crucial to differentiate between LUTs and “looks.”
A LUT primarily focuses on contrast, brightness and color cast changes offering a more technical adjustment.
In contrast a “look” encompasses various elements including sharpness and softness contributing to the overall personality or feel of an image.
Drawbacks of LUTs
Despite their power and efficiency LUTs have limitations.
One significant drawback is their uniform effect across the entire image.
Everything in the image will be transformed by the LUT and one of the most common downsides is the possibility that skin tones in the image will be badly affected.
You can’t apply specific shape information or create subtle vignettes with LUTs however as in the case of skin tones already mentioned there is a workaround.
This involves adding a mask around the skin tone areas to isolate them and creating a motion track to follow those masked shapes as they move in the frame.
Another workaround that has recently appeared is a feature that utilizes A.I. to protect the skin tones from the effects of the applied LUT.
Currently this is a feature found in the Filmora video editor as you can see in the video below but will most likely roll out to others soon.
1D vs. 3D LUTs
Understanding the distinction between 1D and 3D LUTs is essential as often you will see LUTs referred to without any designation as to which one is being discussed.
A 1D LUT focuses solely on brightness by manipulating the values of the whites, the blacks and the contrast levels making it suitable for transformations like log to linear footage.
On the other hand a 3D LUT covers three dimensions – the red, green and blue channels – making it ideal for comprehensive color changes.
The choice between them depends on the specific adjustments your footage requires.
Where to Find Different Types of LUTs
The internet is a treasure trove for LUT enthusiasts.
Numerous websites provide a variety of LUTs from basic to intricate catering to different preferences.
It’s crucial to distinguish between 1D and 3D LUTs – the former transforming a single value setting, while the latter allows for more control over color values.
How to Use LUTs
LUTs require some kind of software for application and the process for adding and deploying them varies depending on the software being used.
Most modern video editing software allows for the use of LUTs within their color correction/grading modules.
Generally they come with a set of pre-loaded LUTs plus the ability to add your own LUTs to the correct place in the effects library.
Some of the more advanced software allows you to apply color corrections or grades to footage then save those settings as a LUT.
As this is a software specific action it is best to check the maker of your software for instructions on how to add more LUTs to your collection.
The Practicality of LUTs in Color Correction
Whilst LUTs offer a precise mathematical and consistent approach to color correction it’s crucial to understand that a single LUT cannot cater to all shots.
You simply cannot rely on a LUT to correct footage on a “one size fits all” basis.
While LUTs are powerful tools they cannot alone salvage poorly shot footage so getting the best possible footage in the first place should be your priority.
Even though LUTs are often mentioned in term of color correction this is not really where they do best.
LUTs are for more applicable in the world of color grading where you as a video maker are seeking to create a uniform appearance across multiple clips.
Original post What Is a LUT – A Guide for Beginners
