Vray - Conflict with ocean horizon, VrayEnvironmentFog and VrayAerialPerspective

Hello,

I have a camera that moves from underwater to above water.

I use VrayEnvironmentFog to create rays of light underwater. But once the camera goes above the water the ocean (Phoenix Static Mesh) there is a hard edge to the sky, ocean and horizon.
So I use VrayAerialPerspective and that solved the ocean horizon, but messes up the underwater view.

Is there any way to disable VrayAerialPerspective affecting below the water (Below Z-Axis)? There seems to be no setting for that.

If there is a more proper method, I would appreciate any advice.

Thank you,
Cyril

Sorry to say the VRayAerialPerspective doesn’t have a control parameter for the “zero”. We have an improvement request (internal bug-tracker id: VMAX-12415) logged though.
One workaround that comes along is to apply the effect in post through a VRayAtmosphere, masked with a VRaySamplerInfo RE set to “Point” and a coordinate system set to “World”. Using only the blue channel of the element (and clamping it to 0-1) should give you a mask of objects above 0.