So I have been looking into physically-based BRDFs for some time now, and have observed a perplexing trend. The companies that post the papers always seem to use a ridiculously high specular power (eg. Treyarch for COD BO uses 8192 for lights, 2048 for environment maps) when using a Normalized Blinn Phong NDF. This seems strange to me, especially since I have read that these powers are for extremely rare, super-polished mirror surfaces. Also, it means that they have to store a high-res mip level in their prefiltered environment maps that will take up a lot of space but almost never get used.
Up until now, I have usually settled for a maximum spec power of 1024 for my analytical lights, and 256 for my environment maps. For my bloom, I have been using a threshold of 1.0 and additive blending (what Unity provides).
Whenever I test these specular powers myself, it causes the resulting specular highlight intensity to shoot up so high that my bloom goes crazy. In particular, as my camera moves I get very distracting flashes of bright spots on sharp model edges that appear and disappear in a very annoying way.
1.) What is the incentive for using such high powers?
2.) Am I doing my bloom theshold wrong, and should I move it up?
3.) Is this a consequence of the Bloom blending mode?
Any help would be most appreciated.
Edited by n00body, 24 December 2013 - 10:29 PM.