Proper use of .exr file in Vray

[Anonymous]

I recently obtained a photoscanned model from a service I subscribe to, and it uses a .exr file for it's displacement map.  This is my first time encountering a .exr, and a brief googling tells me it's a type of high dynamic range image, but that's the extent of my knowledge on the file type.

So as I set up the material using this .exr, is the proper procedure to select a "bitmap" image type in the Vray material, or should I use a "VrayHDRI"? (or some other type altogether?)

I'm inclined to think the former would treat the .exr like an 8bit image, but that's just a guess on my part.

[Francisco_Penaloza · Accepted solution]

So the use of EXR is because the normal map was created to be used as Vector displacement, this is like regular Normal maps but with displacement combined, this gives you the option to not only push the mesh in one direction but on all three axes. That's is also why is using a High Dynamic Range format, because it goes beyond 8 Bits.

To make it works be sure to use the VRay normal shader with the VRay HDRI loader. You could use the default 3D Max bitmap shader but if you are using  V-Ray render, better keep using its own shaders.