> For the complete documentation index, see [llms.txt](https://docs.tachyon.video/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tachyon.video/user-guide/4.-programming-a-show/timeline-editor/screen-and-layer-timeline-properties.md).

# Screen and Layer Timeline Properties

Three toggles and a slider are located to the right of the Screens and the Layers in the Timeline. They can be used in the following ways to affect both Screens and Layers:

![](/files/-MZO1w2MI6cru0HGyC-M)

## Cancel Rendering for a Screen or Layer

* **`Click`** on the **Lighting** toggle to cancel all image rendering for its corresponding Screen or Layer on the connected Display Servers.

{% hint style="info" %}
Cancelling image rendering makes manipulation invisible in its corresponding Layer or Screen.
{% endhint %}

## Lock a Screen or Layer

* **`Click`** on the Lock toggle to prevent any modifications to its corresponding Screen or Layer.

{% hint style="info" %}
The Lock prevents unwanted changes.
{% endhint %}

## Hide a Screen or Layer

* **`Click`** on the Eye toggle to turn its corresponding Screen or Layer to black.

## Modify Alpha for a Screen or Layer

* **`Click`+Drag**  the Alpha slider to modify the alpha channel value for its corresponding Screen or Layer.

![](/files/-MZO2SLuCAHYt3bjwPUm)


---

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