Deep expression to get a better 2D fog effect

This node is pretty straight forward. Normally, when we build multi cards with noise pattern in nuke, we have limitation to move camera, flickering will show up when cards passing by the camera. like below

Force the volume for each card as step one, and apply this deep expression as step two, then job done. Every card will fade accordingly when they close to camera.

It can introduce more interesting look with 2D fog elements on each card.

Happy Comping!