this just happened to me once and i'm not certain when exactly it happened, it was somewhere between chapter 5 and 7 i believe
i was standing right in front of the roanoke's airlock and grabbed the door with kinesis to open it when i dropped through the ground i was standing on
everything around isaac became black, while he dropped further and further down, becoming smaller and smaller until he was just a mere pixel in the center of my screen. I guess the camera was still located where the airlock was, with its focus point on isaac, which would explain the effect of isaac becoming smaller and smaller the further away he got
i had to reload the game because he didn't die he just kept falling down, never happened since