What is a ZDepth?
When an object is rendered, the depth of a generated pixel from the camera is given a depth value. These are normally clipped to an value set by the artist (example: The closest object is 1′ and the farthest object is 30′). Pixel behind an object are referred to as being z-culling.
What is it used for?
A ZDepth element when brought into a composting (Nuke, Photoshop, AE) program allows a few post effects to be applied which are normally expensive and time consuming when done in a 3d software. Some of these effects are:
- Adding in fog
- Adding in depth of field
- Clipping/Masking objects in 2d
|The RBG Render|
|The Z Depth|
|Adding post fog effects|
|Adding post depth of field effects|
|Adding a clipping by distance effects|
Common problems and solutions:
|While this may not seem right, you do NOT want to apply filtering (Anti Aliasing)|
Lets see what both filtering anti aliasing are on and off
Correct with filtering anti aliasing off.
|Wrong with filtering anti aliasing on. See those edges and the odd render effects in the blur?|