The post over at Hivewire that moogal mentioned sounds like one of mine. I remember bagginsbill guiding me through the creation of the realistic falloff depth cue shader on the CGBytes Poser material room forum (the node knows?) and posting a screenshot of the complete shader over there.

But that forum seems to have disappeared.

I'm fairly sure that I have all the information including an MT5 on my laptop, but that's at home whereas I'm not. Not sure how long you'll have to wait though, so posting a screenshot of the atmosphere shader you downloaded as bagginsbill suggests may be the quickest.

---

The 3Dcheapskate (also available in DAZ and HiveWire3D flavours) 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.