With the new light switch feature you can turn the lights on or off by simply holding the capture button for 2 seconds. This can be useful if you want to remove the light from your image capturing or use the camera in pair with a transilluminator.
To check if your camera has the light switch feature, look at the serial number on the handle. If it starts with an "N", you have the light switch feature. If not, you have an older model that does not have this option.