# Luma Key

*Texture Luma Key* is a very useful node designed to mask pixels based on a given threshold. In practice, it is used to create a composite based on the luminance levels of the incoming texture.

<div align="left"><figure><img src="/files/XcxPI7NaNcPQvNx4VvLI" alt=""><figcaption></figcaption></figure></div>

## Setup

To use the node, you first have to insert it in the *Layer Layouts*. You can find it in the dedicated *Search bar*, under **Utilities -> Texture** collapsible.

<div align="left"><figure><img src="/files/v9Clzm9MHjM5VXCmcpOK" alt=""><figcaption></figcaption></figure></div>

Give the *Texture Luma* node a *Texture input* and connect it to an active *Lifeline*.

<figure><img src="/files/audhXB5R190IqxiIpSCf" alt=""><figcaption></figcaption></figure>

All pixels from the incoming *Texture* whose brightness is above the *Luminance value* will be masked. This node is often used in combination with other Texture nodes, such as the *Texture Blend* node.

<figure><img src="/files/MSmN4HUVG2I5lEpfg8xC" alt=""><figcaption></figcaption></figure>


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