Hi,
for exterior renders with a decent amount of sky visible, it's very efficient for speeding the render up to create a render regions for sampling only the areas that are needed - so to say exclude the sky from sampling..
Most of the time, this corresponds with alpha mask of the scene ...
Would be very very useful to be able to just "enable sampling based on alpha mask" in one click.
While working mostly in architecture with geometry in perspective, crating the regions is very very boring...
See attached image.