Apply the Apply Color LUT effect to a layer to transform
the colors of the layer according to a color lookup table (LUT).
LUTs are sometimes used to perform manual color correction or color
management tasks.
Note: In general, within After Effects, color management is performed
using a standard workflow using ICC profiles, not color LUTs. (See
Color management.)
This effect works with 8-bpc, 16-bpc, and 32-bpc color.
When you apply the effect, you are prompted to choose a .3dl
or .cube LUT file. You can also change the LUT loaded into an instance
of the Apply Color LUT effect by clicking Choose LUT in the effect’s
controls.
In After Effects CS5 (with the 10.0.1 update installed) and later,
the Apply Color LUT effect can use .3dl files with floating-point
values or 3DMESH/Mesh keywords, or those saved from an ASSIMILATE
SCRATCH system (i.e., that have SCRATCH in the comments at the top
of the file). For more information about changes and fixes regarding
color LUTs in After Effects 10.0.1, see the After Effects region of interest blog.
A LUT can be visualized as a three-dimensional coordinate system
(a 3D cube), with each axis representing color transformations for
the range of all values for a color channel. Points along each axis
define the color transformations for each color channel. After Effects
can read and use 3D LUTs that have all three axes the same length
(same number of points), with each axis containing 64 or fewer points.
For example, After Effects can read and use a 17x17x17 3D LUT.

You can create LUTs using commands in the File
> Export menu—such as Autodesk > Smoke (3dl)—in the full interface
of the Color Finesse plug-in.