I have scene with two objects (main object and reflective plane).
I have enviroment reflection and I don't want plane to reflect enviroment i only want plane to reflect main object.
I made constribution map just for the plane.
In this first picture i make ibl node , and as suspected ibl node reflects on plane.
This plane reflection pass.
That is ok.
Then i deleted ibl node , made lookupspherical node , connect this node to enviroment slot of main object shader.
And i get this.
This is what i don't understand.
I get this reflection from enviroment on plane where "main object" is ,that is reflection is seen througs main object alpha channel.
Maybe there is logic behind this , but i don't understand what is going on.