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Introduction
This document discusses how the use the LUT Measure.
Basics of LUT
The goal of using LUTs is to color-match the Digital Extension with the studio camera's video input.
There will always be a color difference between the real and the extended image. Firstly, the real image is shown on the LED wall; secondly, it is seen through a camera. Both of them entertain some degree of color transformation.
Aximmetry provides a LUT Measure feature that can automatically calculate the color transformation's value (between the video input and video output), and use it to correct the Digital Extension's colors to match that of the studio camera's video input.
NOTE: As a manual adjustment option, you can use the DIGIT EXT ADJ panel's usual Brightness / Contrast, etc., controls to get the Digital Extension's colors closer to the LED walls' colors. To learn more about this, please refer to the following documents:
Digital Extension Adjustments
Starting the LUT Measure Process
On the LEDWALLS control board, click on the power button present on the LUT MEASURE control panel:
At first, you will see a grey image with an Aximmetry logo in its middle projected on the LED Wall in the Frustum area:
Select the LUT MEASURE control panel, then on the Pin Values panel specify the target folder and filename parameters:
Then click on the play button to begin the LUT Measure process:
The system will go through the 32 x 32 x 32 different colors, displaying and sampling an 8 x 8 portion at a time. The whole process takes only a couple of seconds.
At the end, a .cube file is saved containing the 32-sized cube LUT. The same file will be automatically specified as your LUT file at the DIGIT EXT ADJ control panel's LUT pin value.
IMPORTANT: The displayed colors go through the frustum ADJUSTER X control panel of the given LED wall. Therefore, please note that a given LUT file is only usable with the same physical settings of both the LED wall and the camera, and the exact same settings of ADJUSTER, so if you adjust the aperture, ISO, or any other setting that affects the brightness of your video input after the LUT measurement, you will have to redo the measurement.
