Photos

This page is a collection of interesting photos that I have taken.

(April 2025) Green Waters

I took the following photo of the sea around the island of Capri. We can see the how the color of the water changes from green to turquoise to blue as a function of the water depth.

A similar effect occurs at Emerald bay in Lake Tahoe.

While one may attribute green color to underwater vegetation, that is not the case in these locations. The green color disappears when the sky is cloudy.

(May 2020) Sun dogs and 22-degree halo

The following two photos were taken with an iPhone camera. This is not a rainbow for a couple of reasons: in a rainbow, the curvature-color correspondence is different, red is on the convex side. Also, rainbows have their center about the point opposite to the sun. Instead, I think this is a different phenomena called sun-dogs and the 22-degree halo, caused by hexagonal ice crystals in the clouds. (link)