Skypools on Surface Waves
Summary Author: Patti Weeks
Shown above is an abstract image containing distorted sunlit reflections of the sky, clouds, and a fishing dock on a pond stirred up by the wind. The optical result is a mixture of wavy lines, swirls and a complex phenomenon called skypools. However, viewing the picture from a different perspective, it could be said the abstract photo looks like a landscape consisting of meandering rivers, oxbow lakes, ponds, sandbars, and cliffs.
Skypools are seen as distorted swirls and pools on the surface of gently moving bodies of water. The wind creates vibrational surface waves that move the water up and down. From this motion, crests and troughs are formed in the constantly changing curvature of the water surface. We do not see straight line images, as normally seen in the spectral reflection of a mirror, but instead diffuse reflections are visible on the waves at various degrees of convex and concave angles in addition to overlapping lines of sight from point-to-point. The distorted images change from moment to moment, meaning if another viewer at a different vantage point took a photo at the exact same time as this photo, the image would be completely different. Watch this video to see the motion of the ever-changing skypools and distorted reflections. Skypools are generally seen when the angle of the viewer’s sight is greater than 15 degrees, which coincides with when most of the surface of the wave is visible. Only when the wind stops can the water return to a relative state of equilibrium. Photo taken on February 10, 2022.
Photo details: Apple iPhone 11 Pro; 6 mm, f/2, 1/122 second exposure, ISO-32
River Park North, Greenville, North Carolina Coordinates: 35.627, -77.360
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