50mm/f1.8 AF-S Distortion Study

I captured our local swimming pool and club house with the 50mm/f1.8 AF-S on a D700 (FX-format) body. I added the red rectangle to help us visualize the amount of distortion from this lens.It should be clear that the water level in the swimming pool is bowing outward a ittle away from the center of the frame. The amount of distortion is very slight. The same is true for the sides of the club house building.