Creating A Depth Map Using The Atmosphere 'Depth_Cue' (shorter version of the post! :)
( Doing DoF inside Poser already covered - http://www.renderosity.com/mod/forumpro/?thread_id=2888795&#msg4193643 )
- The usual 'turn off the lights' approach:
http://www.renderosity.com/mod/forumpro/?thread_id=2821053#msg3760022
http://forum.runtimedna.com/showthread.php?26700-Depth-Map
- turn of all lights
- activate "DepthCue_On" (Atmosphere material)
- set DepthCue_Color to white
- set DepthCue_Start and _End distance (try 0 and 1000 inches, open result in GIMP/whatever, check min/max grey, put those figures back into Start/End, and rerender)
- disable glowing materials (ambient, reflection, alternate diffuse, others???)
- render (disable IDL/SSS if you use those to speed it up)
N.B. Don't forget to back up your scene first if you start changing the materials.
- Plug a P-Node into Atmosphere depth cue, leave the lights on, and don't touch any other materials...
http://www.renderosity.com/mod/forumpro/?thread_id=2821053&#msg3760699

The 3Dcheapskate* occasionally posts sensible stuff. Usually by accident. And it usually uses Poser 11, with units set to inches. Except when it's using Poser 6 or PP2014, or when its units are set to PNU or something else.
*soon only to be available in two flavours - DAZ and Renderosity