The Filter tab allows you to control which geometry GeoRadiosity draws.

Show all LODs	Show all meshes simultaneously.
Show Target Geometry	Show only the meshes that are included in the radiosity computation. The screenshots below show the Arches scene with Show Target Geometry switched off and then on to display detail and target meshes, respectively.
Draw Dynamic Objects	Enables / disables drawing of dynamic objects within the scene.
LOD	Forces GeoRadiosity to draw objects with the specified LOD level.
Show Cull Tests	Shows cull tested bounding boxes. This mode can give a visual indication of scene complexity.
System / Geometry / Mesh / Tri list	Filter rendering of the systems > geometry > meshes > triangle lists scene hierarchy by index. For example, if there are three systems in the scene, setting the System filter to `1` displays the second system only. Setting the values to -1 disables the filter.
Mesh properties	Displayed only when filtered to a mesh; that is, the Mesh slider is set to > 0.

Show Target Geometry off	Show Target Geometry on

You can also filter using the context menu. Right click on the required part of the scene and select Filter to System/Geometry/Mesh/Triangle list from the context menu.