basically I need a way to disable filtered/transmitted light from interacting
with global atmospheric media for a specific object in the scene. When the
object in question color have f and t  greater than 0, some very strange
lighting affects occur in the media. more details info below.

the situation:
==============
I'm rendering two objects, and a third used for creating rays in a fog like
media. 1) a set of spheres and cylinders, 2) a surface defined by imported
mesh2. This needs to be partially transparent. 3) copy of 2's mesh2, but
transmit and filter 0.

object 1,2 has a light_group with a set of different lights. both these light
groups have global_lights off. each light in both groups have media_interaction
off.

The purpose of object 3 is create a pattern of rays through the fog. There's a
spot light positioned facing the camera behind a copy of the mesh2 surface.


the issue:
==========
when object 2 is in the scene it affects the rays through the fog like media. In
object 2 f and t are non zero, and the impact is like refraction or focusing.
making some bright rays. This is unexpected because all lights on this object
are set not to interact with the media. also global_lights are off in his
light_group.

I need this not to happen. It doesn't if I set object 2 f and t 0, but I need
them non-zero.

Any idea why this would happen, how I can have object 2 f,t non-zero, and not
impact the rays through the fog??

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