Resolution? Bandwidth? Lack of a better alternative? Diminishing returns? For the last 15-20 years, 16XAF has been the standard maximum value in games and drivers with no real challengers or competitive functions. While it works well enough in most situations, there do seem to be instances where 16XAF is not sufficient as a maximum value. My understanding is that AF doesn't use the same filtering strength across an entire scene, but rather it applies the highest filtering level to "only distant highly oblique pixel fills" when it is needed. Perhaps different combinations of AA+AF accommodate this already. Just curious.