I guess as he decended, the air lifted the feathers on his legs, making them appear much larger. He just plopped on the water, and then, took off.
The Bald Eagle is Haliaeetus leucocephalus, the Osprey is Pandion haliaetus, they are closely related. The Bald Eagle is bigger but the Osprey is “badder” LOL. I’ve seen them snatch a fish from an eagles claws, in flight.