Texture Gradient, Overlap, and Aerial Perspective Monocular cues are used to gauge distance of objects in a photograph. The rows of tulips appear crisp in the foreground but become increasingly fuzzy in the background, an example of texture gradient. Similarly, the rows of tulips at the top of the image are just blurs of color, creating an impression of even greater distance through aerial perspective. And, the yellow tulips are perceived as being closer than the gravel pathway and green stems that they overlap.

photomadnz/Alamy