> For the complete documentation index, see [llms.txt](https://chaoses-ib.gitbook.io/directory-opus/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://chaoses-ib.gitbook.io/directory-opus/manual/preferences/preferences_categories/viewer.md).

# Viewer

This category contains options that affect the Opus image viewer - both the [standalone viewer](/directory-opus/manual/additional_functionality/viewing_images.md) and the [viewer pane](/directory-opus/manual/basic_concepts/the_lister/viewer_pane.md).

* [**Standalone Viewer**](/directory-opus/manual/preferences/preferences_categories/viewer/standalone_viewer.md): Contains options that affect the behavior of the standalone image viewer.
  * [**options**](/directory-opus/manual/preferences/preferences_categories/viewer/standalone_viewer/options.md): More options for the standalone viewer.
  * [**Size And Position**](/directory-opus/manual/preferences/preferences_categories/viewer/standalone_viewer/size_and_position.md): Options that control size and position of the viewer.
  * [**Mouse Buttons**](/directory-opus/manual/preferences/preferences_categories/viewer/standalone_viewer/mouse_buttons.md): Contains options that affects how your mouse buttons behave in the standalone image viewer.
  * [**Marked Pictures**](/directory-opus/manual/preferences/preferences_categories/viewer/standalone_viewer/marked_pictures.md): Options that control the [image marking](/directory-opus/manual/additional_functionality/viewing_images/image_marking.md) system.
  * [**slideshow**](/directory-opus/manual/preferences/preferences_categories/viewer/standalone_viewer/slideshow.md): Slideshow options for the standalone viewer.
* [**Viewer Pane**](/directory-opus/manual/preferences/preferences_categories/viewer/viewer_pane.md): Contains options that modify the behaviour of the viewer pane.
* [**Viewer Plugins**](/directory-opus/manual/preferences/preferences_categories/viewer/viewer_plugins.md): View and configure your installed viewer plugins (third-party components that can add additional image formats to Opus).