Hi @Anonymous
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Please click HERE to see the video which demonstrates how to define artificial lighting for a rendering in Revit and how to adjust the exposure.
In the Artificial Lights dialog, under On/Off, select individual lighting fixtures or light groups to include them in the rendered image. Clear the check boxes to omit the lights in the rendered image.You can also enter values in the Dimming column to dim individual lighting fixtures or entire light groups.
See attached images below:

To dim lights
- Open the 3D view to render.
- Define render settings.
- In the Rendering dialog, under Lighting, for Scheme, select a setting that includes artificial lights.
- Click Artificial Lights.
- In the Artificial Lights dialog, in the Dimming column, enter dimming values for light groups or individual lighting fixtures.
Enter a value between 0 and 1 to indicate the relative amount of dimming. A value of 1 means that the light is completely on (not dimmed). A value of 0 means that the light is completely dimmed (off).
Note: If a lighting fixture is a nested family that contains multiple light sources but is not shared, you cannot dim individual light sources in the fixture.
- Click OK.
- To see the effects of dimming the lights, render the image.
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