> ## Documentation Index
> Fetch the complete documentation index at: https://docs.spine.altician.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Window/Level

> Adjust brightness and contrast of the volume

## Activating W/L Tool

Click the **W/L** button in the toolbar to activate the window/level adjustment mode.

<img src="https://mintcdn.com/altician/0YBh5K6l-27QqsAD/images/wl-tool.png?fit=max&auto=format&n=0YBh5K6l-27QqsAD&q=85&s=ad46b96a439fa93774ddf18c981c03c8" alt="Window/Level tool active" width="1920" height="1080" data-path="images/wl-tool.png" />

## Usage

With the W/L tool active, click and drag on the viewport:

| Drag Direction | Adjustment                |
| -------------- | ------------------------- |
| Left / Right   | Window width (contrast)   |
| Up / Down      | Window level (brightness) |

## Reset

Click the **Reset** button to return to the default window/level values.

<Warning>
  Activating W/L automatically deactivates **Pointer** and **Ruler** tools. Only one interaction tool can be active at a time.
</Warning>