Ali Fatoorechi

Please try tomorrow's H21.0 daily build for the Cage Mesh Topology match fix.

Also note that rather than PolyExtrue node, you may need to use Peak node for offseting the Low res mesh inorder to preserve the topology.

It actually is working as expected, sorry. I was playing with MIS Bias instead of Portal MIS Bias.
Please try the hip file I shared on the previous post and change the option on the dome light Karma tab to see the effect.

There are two node branches in the hip file that demonstrate the old (via Render Geometry Settings) and new style (Portal Light HDA)
of setting up Portals.

Please report a bug if this doesn't help. Thanks.

Hi,

Yes for high contrast area setting Portal MIS to -1 (sampling environment map) may be more beneficial.
However the option seems to be broken when using Portal Light HDA (attached hip file).
I will investigate it further.

It would be great if you could log a bug and attach a sample model too. Thanks!