I created a new cubemap. All the files have the same size and are png. If I replace the helipad one with my own, no visible effect happen on my model. When I raise the intensity, the skybox gets lighter but nothing happen on my model.
Any clues as to why this happen?
Please post a link to a reproducible of your problem.
I found the solution here : https://developer.playcanvas.com/en/user-manual/graphics/physical-rendering/image-based-lighting/
Prefilter button is available on CubeMap asset in the Inspector, it is mandatory to enable IBL on physical materials using a CubeMap.
This fixed my problem.