The attached video demonstrates the perceptual phenomena of change blindness. Our visual focus and expectations cause us to be "blind" to the fact that more than the expected changes occurred in our perceptional field. Four other factors changed during the color-change card trick including the male's shirt color, the female's shirt color, the tablecloth color, and the background color. When first watching the video, attention is focused on the card trick, and often will not notice the changing scene colors. This poor ability to detect discrepancies in our visual field was due to change blindness.
This video shows the results of eye tracking technology to determine the focus of viewers to better understand how change blindness could have occurred.