Within the camera settings, you are able to configure the night vision (IR) settings. Navigate to the camera where you want to adjust these settings, go to the Camera Settings and Details and look for the IR settings.
The IR LED setting is to enable night vision. The default mode is to keep it on Auto, but there are times when you might want this off. The most common scenario is when the camera is looking out a window. By disabling the IR LED, you won't get a reflection off the window and the camera will be able to see out of it at night.
Below is a complete table of different modes.