Mysterious Skypools
June 14, 2017
Photographer: Patti Weeks
Summary Author: Patti Weeks
As shown above, how light is reflected can at times be quite confounding. A stable, flat reflective surface, such as an everyday mirror, reproduces a relatively exact, albeit reversed, image in what is called specular reflection. The uneven surface of moving water, on the other hand, distorts its reflected image and results in the diffuse reflection of the surrounding environment at many different angles.
On occasion, the eye sees the reflection of the sky, land and/or nearby objects on the surface of gently moving water as distinctive ovals of color. These are called skypools, a complex optic phenomenon. As the moving water dances in sunlight on a pond, lake or river, the subtle surface waves alternate between concave and convex folds, producing undulating pools of colored light. Interestingly, the organization of the actual reflected objects takes on an entirely different order as the reflected light is distorted by the changing curvature of these pools, revealing parts of the images right side up and some parts inverted. Skypools are best noticed at a viewing angle of higher than 15 degrees so that the entire surface of the waves can be observed.
This photograph captured the distorted reflection of a boat’s bow and the red, white and blue of an unfurled American flag, so rather than skypools, these might be called boatpools and flagpools. The photo at left shows a normal view of the boat and flag. It doesn't alter the mystery of the skypools but perhaps makes them more understandable to the viewer. Luckily, you don’t have to completely understand them to enjoy their mystery and beauty. Yellow-bellied sliders sunning on the rock in the foreground also seem to be entranced by theses wondrous skypools. Photo taken September 5, 2016.
Photo Details: Top - Camera Maker: SONY; Camera Model: DSC-RX100M4; Lens: Sony 24-70mm F1.8-2.8; Focal Length: 25.7mm (35mm equivalent: 70mm); Digital Zoom: 2.000x; Aperture: ƒ/4.0; Exposure Time: 0.0080 s (1/125); ISO equiv: 125. Insert - same except: Lens: 8.8-25.7mm ƒ/1.8-2.8; Focal Length: 14.7mm (35mm equivalent: 40mm); Aperture: ƒ/5.6; Exposure Time: 0.0016 s (1/640).