Windows Hello facial recognition can automatically brighten your screen to help sign you in when you're in a dark or dimly lit room. This article explains how the feature works and how to turn it on or off.
How does low light sign-in for Windows Hello facial recognition work
When Windows detects that ambient lighting is too low during a facial recognition sign-in attempt, Windows Hello will temporarily increase your screen brightness so the display acts as a light source to illuminate your face. After sign-in completes (or the attempt ends), your screen returns to its previous brightness level.
Screen brightness is increased only when it's needed, that is, when the IR camera can see your face but there isn't enough light for the color camera.
How to turn Windows Hello automatic screen brightness off
This feature is turned on by default, but here's how to change it in Windows Settings:
- Select Start > Settings > Accounts > Sign-in options.
- Expand Facial recognition (Windows Hello).
- Turn off the "automatically adjust screen brightness during face recognition" setting.
Note
If you turn this off, Windows won't change your screen brightness during face sign-in, and facial recognition sign-in may not work in darker environments. If face sign-in doesn't succeed after the brightness increase, you can still sign in with your PIN or fingerprint. The brightness change is temporary and reverts automatically—you don't need to reset it manually.