Possible to adjust brightness of HMD and PC display independently?

The game I'm working on right now frequently uses very dim lighting (or even no lighting, to create pitch-dark shadows), and it seems like in low-light scenes the view inside the headset is often much, much more visible than what outside observers or recording software can see on-screen. Objects in very, very dim lighting might be quite visible to someone in the headset, but to outside observers, it can look nearly pitch-black. Is there a way to adjust the brightness of the two independently, so that observers watching on the monitor get a clearer view of what the player is seeing?