The other day, as I was pouring a cup of water, I looked straight down into the cup.  As the water started to near the top of the cup, I stopped pouring.  Didn't want it to spill over.

As I stepped away and looked at the cup, I realized there was still a long ways to go until the water reached the top.  What I saw from the top was not the same as what I saw from the side.  Same cup, totally different view.

Are you looking from the top or from the side?