Falloff map in Fresnel mode is not supported in Refract IOR slot
This message is triggered when the scene contains a Corona Material which has a 3ds Max Falloff map set to Fresnel mode plugged into one of its channels (for example Reflection IOR or Reflection Color). For internal architecture reasons, Corona cannot support the Fresnel formula used in the 3ds Max Falloff node.
- Remove any Falloff maps set to Fresnel mode from any slots of your materials.
- If you need to map a material's Fresnel IOR based on a texture, you can use:
- The Fresnel IOR slot of the Corona Legacy Material
- The IOR slot of the Corona Physical Material
- The best solution may be switching to the Corona Physical Material which provides better control over a material's IOR, specularity, or metalness.