Obviously, this is the same lady on the left and on the right.  Clearly, she appears larger on the right than on the left.  This is the result of looking at her in the famous illusion known as the Ames Distorted Room.  A diagram of this room appears below.

The photos of the lady above were taken through the viewing hole in the front wall of the Ames room.  You can see that the left rear wall is further from the front wall than is the right rear wall.  Moreover, the left rear wall is taller than the right rear wall.  The two vertical lines are identical in length.  You don't believe me?  Get a ruler and measure them.  These room distortions result in the object of known size (the lady) appearing a different sizes.

When the lady was on the left she truly subtended a small visual angle than when she was on the right.  Consequently, it makes sense that she would appear larger.  But she is also larger than other known objects, e.g. the window.

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