What is the SceneTexture: SceneDepth node of postprocessing?

I want to know how the scene depth node works.
Does this node returns the distance from opaque object to the camera center line ? (line passing through the center of camera)

I’ve been trying to find the answer to this as well, and as far as I can tell it gives you the distance from a translucent material to the material behind it on a per pixel basis. (Calculated from the Camera to the pixel, to the pixel behind it).

But I am not sure, what I really want to know is what is the difference between the SceneDepth node and the SceneTexture:SceneDepth node?

SceneDepth gives you depth of the scene behind current fragment. SceneTexture:SceneDepth allows you to sample scene depth at any point.

Thank you, it’s clearer now, I do still have one question.
You said that sceneTexture:SceneDepth allows you to sample scene depth at any point, however, SceneDepth also has a UV input, does it not allow you to change to location of the sample?

Or is the SceneTexture UV sample based on the screen position while the SceneDepth UV refers to another point on the object itself (based on it’s uv’s), or something like that?