Xochimilco Ride - Parque Ecologico, Mexico City

@danthro: Hello Danthro! Thanks for the comment and for asking. I use a polarizer and expose for the sky. I shoot raw so I have greater flexibility to selectively bring the dark areas out later in the post processing. I simply darken the entire image with a curve and then erase the areas of the layer I do not want as dark. Thus I get the contrast in the sky. The bw is via channels. Cheers!