Not only does the cropping change the photo from horizontal and fat to tall and narrow, it helps to focus attention on the most interesting part of the photo -- the carving -- while still showing enough background to give the image context.
Crop to Change the Shape or Orientation Example: Cropping to turn horizontal image to vertical
By Jacci Howard Bear, About.com Guide
Before: The carving almost fades into the trees. After: The vertical crop accentuates the vertical elements of the foreground and background.
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