Brian's examples are really superb -- I especially like his one of an amphitheater in Athens -- in part because he takes exquisite care to custom "mask" (designate) the areas of a photo that are to be in focus or not in focus in the end product. For the most part, while fooling around with the process in Photoshop yesterday and today, I used the less-convincing but easier and quicker method that online tutorials (such as this one from "Photo Infos") instruct. Only one of the following tilt-shifted images involved custom masking; can you tell which one it is? Please click on the images to see larger views -- the effect might not even be noticeable at the sizes on this page.
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The brown building at lower-left is the Paramount building, which is dwarfed by a crowd of bigger buildings from this vantage point today. The blue building at center -- the original McGraw Hill building, an art deco icon built at the same time as the Empire State Building -- is not even visible from the Top of the Rock now!
So... now you're ready to appreciate Brian's professional-grade tilt-shifts! Enjoy!