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Hybrid Images by Sumi Mudgil

For my illusion, I decided to create a hybrid image. Hybrid images are images that when viewed at different distances are perceived differently. This is achieved by combining the high spatial frequencies of one image with the low spatial frequencies of another. As you gradually zoom into a hybrid image, it transforms from one image to another. For example, when viewing my image from up close, you should see MTL, with varying, random shadows in the background. As we zoom further out, you may see an image that looks like a more feminine version of MTL. And finally, when the image is zoomed out or viewed from afar, you should see Professor Grill-Spector.

This illusion captures how our visual system interprets visual information in terms of spatial frequencies. When viewing an image from afar, we only appreciate the lowest spatial frequencies, which provide us the general shape and contours of the object and luminance variations in it. Conversely, when we view objects up close, we see high spatial frequencies, which provide us finer contours and better details. This makes sense, as when we see an object far away, we cannot appreciate its details (only see lower frequencies); whereas, when we see an object at a closer distance, we can appreciate its details such as texture, sharpness, and finer contours (higher frequencies).


Illusory Motion by Clare Tandy

This illusion shows two examples of illusory motion induced by peripheral drift, the rotating circles in the upper segment and the rolling cylinders in the lower segment. The motion is most prominent when looking to the side of the image and the movement being processed comes from the periphery - when looked at directly on, the movement appears to stop.

This illustrates the different levels of visual perception, as well as how overt changes to attention affect how we perceive the world, and based on the most recent research illusions of this type rely on the microsaccades and blinks to trigger the illusory effects. In addition, these movements combine with the ability to perceive motion from pairs of stimuli in different contrasts (the black and white bands on the outside) (Otero-Millan, et al.). T his also helps explain why they always roll or rotate in the same direction, from dark to light, because the difference in contrast is consistent.


Ferris Wheel Illusion by Riley Wilson

I made the kind of illusion where one slides a clear plastic sheet with black stripes across an image with many thin vertical lines on it, a nd in doing so creates the illusion of an animated effect on the sheet. I built my illusion in photoshop, by drawing equally spaced and carefully measured black lines into a grating, then using this grating over different cycles of frames for each image, subtracting from the image all parts that would be obscured by the bars on their given frame. I designed a Ferris wheel illusion, to demonstrate that by changing the direction of the grating movement, you could change the apparent direction of the motion of the Ferris wheel.

This demonstrates the mechanism of apparent motion, where went presented with multiple images slightly shifted in rapid succession, our brains perceive one image in motion.


Macaque Illusion by Miguel Patrick Taruc

I implemented an origami (folded paper) illusion, in the form of a custom-illustrated macaque monkey (as an ode to all the psychology experiments involving macaques). As you close one eye (for best effect) and move your head side to side while focusing on the monkey's eyes,the brain is tricked into perceiving that the monkey's face is turning its head and following you.

The illusion depends on the neural mechanisms for facial recognition. We are biased, from experience, to perceive faces as convex - popping out- at us. The ambiguity of the lighting/shading of the macaque and the reliance on monocular cues such as linear perspective allows our brains to be tricked into perceiving the concave face as convex. The folded paper, although convex, still simulates how the dinosaur would look at that particular angle, and so as we move our gaze, we interpret the monkey's head as moving because of this bias. Much like the Thatcher Illusion, we don't realize something is wrong with the face and we interpret it fine until we see the truth: that the face is actually concave.