Why two panels rather than one field
A single flat field lights a face evenly, which is safe and slightly lifeless. Two sources at either side, with one brighter than the other, gives a face shape — that is the standard key-and-fill arrangement, and it is why lit interviews look different from video calls.
The dark centre also stops the screen glaring straight into the lens if the camera is mounted in front of it, which is the practical problem with using a whole monitor as a light on a streaming desk.
- Streaming, where the camera is fixed and the light can be arranged around it
- Recording talking-head video with a bit more shape than a call needs
- Filling shadow on a face lit mainly from one side
Arranging it on a streaming desk
Put the screen behind and slightly above the camera and angle it down a little. Then move yourself, not the screen: the position of the shadow on your face is set by where you sit relative to the light, and that is much easier to adjust.
Around 5000K sits between daylight and tungsten and is a safe default for a room with mixed lighting. Match your other lights if you have any — mismatched sources are what make one side of a face green.
Getting more out of it
Two devices work better than one. A tablet on each side, one brighter than the other, gets you a genuine key and fill for nothing, and each one is a bookmarked link with its own temperature and brightness.
If the result is still too dim, switch the shape to the whole screen — a full field puts out considerably more light than two panels do.