The new formula should be the correct one according to this document (first line p86): https://seblagarde.files.wordpress.com/2015/07/course_notes_moving_frostbite_to_pbr_v32.pdf
The new formula should be the correct one according to this document (first line p86): https://seblagarde.files.wordpress.com/2015/07/course_notes_moving_frostbite_to_pbr_v32.pdf