Behind Windows
Live video right behind your work can be distracting. So while windows cover a display, PanoPaper lets the video step back into a calm backdrop - and brings it back in full the moment you clear the desktop. Set it up in Settings ▸ General ▸ Video ▸ Behind windows; changes show at once.
Dim
Darkens the video, from Off to 80% - even at 80% you can still make out the picture. It starts at 35%.
Fade
Lays the color (see below) over the video like colored glass. The more you fade, the less video shows through; at 100% the display shows the plain color, like a solid-color wallpaper. It starts Off.
Color
Fade's color is black at first. Click the color well to choose another, or click 'Pick from Wallpaper…': the video disappears for a moment and a magnifier appears, so you can click any color of your normal wallpaper - the video then blends right into your desktop.
The two combine: for example, a little Fade in your wallpaper's color with a little Dim gives a quiet, matching backdrop.
With no windows in front
'Also when no windows cover the desktop' (on at first) keeps Dim and Fade when no windows cover a display - after Show Desktop, or on a Space with no windows. Turn it off for the video as is then. It is greyed out while both are Off.
A display counts as covered as soon as a window is open on it - any app's, PanoPaper's Settings window included. Show Desktop moves the windows aside, so it counts as clear.
A calmer frame rate
Behind windows, the video plays at 15 frames per second, which is plenty for a backdrop and saves energy. With a clear desktop, it plays every frame the camera sends. This does not depend on the settings above.
The camera's audio can be quieter behind windows too - see Camera Audio.