The internet is full of little tests and quizzes you can perform quickly to determine if you have what it takes to solve the puzzle. Many of them are quite difficult or are based on the subject’s previous knowledge, but one test is causing concern for a totally different reason.

The test is a vision test designed to determine how well you can see. The test is a simple image with static like what you might to find on a television screen when there’s no signal, only the static is a deep red.

Vaguely hidden beneath the red static is a number, but it is hard to read through the static clearly. It is as if the number is meant to be obscured to the critical point where only those with the absolute best vision can see it clearly.

There is only a single question associated with the quiz, and it is one that even gives the subject a clear guess at the number in the middle of the static. The question is whether the number is 571 or 574. Right away your eyes will fill in the 5 and the 7 in their rightful place, but you’ll notice that almost no matter how hard you try, the last number will remain a mystery. It almost appears equally as a 4 and a 1, but that is impossible.

The static is merely obscuring the area that makes up the difference in the physical shape of the 4 and the 1, but it is actually just a 1.

Optical illusions are images that can be perceived in different ways by the human eye. They are generally characterized by their ability to cause a discrepancy between the image that is seen and the image that is actually present. This discrepancy can be caused by various factors, including the difference in the way that light is reflected off of different objects, the difference in the way that images are presented to each eye, and the difference in how the brain interprets information that it receives from the eyes.

There are a number of different types of optical illusions, and they can be created using a variety of different methods. Some of the most common types of optical illusions include the following:

-The Müller-Lyer illusion, which is characterized by two lines that appear to be different lengths even though they are actually the same length.

-The Poggendorff illusion, which is characterized by two diagonal lines that intersect at the center of the image, but appear to be parallel on either side of the line where they meet.

-The Hering illusion, which is characterized by a set of four squares that are arranged in an “X” pattern on top of a larger square. The squares on the outside of the “X” appear to be displaced inward, while the squares on the inside of the “X” appear to be displaced outward.

-The Kanizsa triangle, which is a triangle that does not actually exist, but is perceived by the human eye due to the way that light is reflected off of the surrounding objects.

-The Ponzo illusion, which is a perceptual illusion that is caused by the difference in the way that images are presented to each eye. It is characterized by two lines that appear to be different lengths, even though they are actually the same length. The line that appears to be longer is located farther away from the other line.

-The Zöllner illusion, which is a type of geometrical or straight-line illusion. It is characterized by two lines that appear to be different lengths even though they are actually the same length. The line that appears to be longer is completely surrounded by the shorter line.