I want to have cast shadows appear on a ground plane to use as elements in a 2D composite. All I want to see in the final render is the shadows cast onto a fairly bright ground plane (or isolated on a photoshop layer, or alpha channel) The object casting the shadows should not be visible.
What would the optimum shadow catcher settings need to be for this?
My test renders produce a solid black object, and the shadows have disappeared from the ground. Alpha channel is blank.
(I have objects that have been extracted from photos that will be composited into new photos/backgrounds. 3D cast shadows could look more realistic than 2D painted shadows)
I didn't know about all the options in Instance Properties. It's common in photo compositing to need cast shadows for imported clipped objects/people. Even for an experienced artist this can take time. This is a powerful tool for this purpose. I have a flock of Bison that will drop into a scene. Each needs a cast shadow. I built a four legged primitive that casts a perfect shadow from a global light with very soft shadows. Thanks Kevin!