So not sure what the "subject" should be but i noticed something very weird. I was doing a test render but didn't want to build out exterior walls so i went for a more studio warehouse with zero opening to the exterior. In doing so i notice that if the time of day change some does my vacuum interior objects - why? See attached images.
The 2:30 am (Night) is rendering correctly for an fully enclosed environment. However, the 2:30 pm (mid day) the object appear to be glowing.
Found this interesting.