Autumn in St. Petersburg

My photo tour in Russia was timed to coincide with autumn, and many of the places we visited were embellished by mostly golden leaves. The brilliant red colors well-known in the Northwest of the U.S. and in Japan and Korea were mostly absent. So, to enhance this picture of 19th century St. Issac's Cathedral in St. Petersburg, I selected a few small areas of the trees and, using the hue slider in the hue/saturation dialog box, I changed some of the yellow areas to red. In addition, the original white sky needed to be changed, so I added gray clouds using a layer mask and the gradient tool so the new sky blended gently with the tops of the trees. I used a 24-105mm lens for the shot, and my settings were 1/250, f/4.5, and 250 ISO.