Wednesday, August 7, 2013

Reflections on gently rippled water

In his 1903 book "Light and Water", Sir Montagu Pollock uses this photo to illustrate an observation of reflections on gently rippled water: "The gentle movement of water in the distance elongates and exaggerates the upright lines of the buildings. In the foreground, the individual ripples become visible, breaking up the reflection of the mountains horizontally."

He explains the elongation of the reflection of the buildings by setting up a series of mirrors to represent the far wavelets, and then tilting them toward and away from the observer. Since the area they reflect shifts vertically, they have the effect of stretching the reflected image downward.
"Light and Water: A Study of Reflexion and Color in River, Lake, and Sea" by Sir Montagu Pollack, Bart (1903) is available as a free download from


Artillory said...

I'm only guessing, but it would seem like the difference in the vertical distortions versus the horizontal distortions are because of the numerical amount of compressions in the perceived wavelengths which are multiplied in the distance whereas only a few can be seen in the foreground. It might be likened to the amount of stretch in an accordion versus say... a fire bellows? In other words there is more capacity for expanded distortion in the distance vertically and less horizontally and vice versa for the near ripples. Its all the same relatively calm water, so this assumes the same wavelengths, near or far, more or less of all the water ripples.

Mara Mattia said...

I don't understand. Where are the mirrors? "A, B, C, & D"? or on the door? I'm looking for tilting mirrors in the illustration. Tilting them toward and away??

Mara Mattia said...

OK, I see it now, duh! :-)