Tilt-shifting is a photographic effect where a faraway shot is artificially blurred in such a way as to give it a depth of field effect usually only found in close-up photography. This is because lenses (cameras and eyes) have different depths of field depending on how far away the object is. [A good demonstration of this depth of field effect is to move your head closer to the screen, close one eye and hold your finger up halfway in between your eye and these words. Focus on the words and you'll see that your finger is fuzzy. Now, leaving your finger where it is in relation to the screen, gradually move your head back and you'll see that both the screen and the finger become reasonably sharp.]
When used properly it can produce surreal shots with a hint of cutesy nostalgia.
Now, wind the clock back to the mid-nineties and to the glory days of lens flares.
An often unwanted effect of photography in bright light was that little orbs (i.e. lens flares) would appear on the photo due to the source of the light hitting the lens directly. It wasn’t long before photo editing programs like PhotoShop realised that some artists were using this effect to give a shiny thing a bit more ‘bling’ and before you could say “Bob’s your sugardaddy” wannabe artists (myself included) were putting lens flares on anything and everything. Including things that didn’t shine. Like fur for example. Want to make your cat look more expensive? Put a big ol’ lens flare on its shoulder.
Return to the present and we have the same thing happening with tilt-shifting.
If you have, say, a photo like the above, the tilt-shift effect works pretty well because when you track vertically up the image the actual horizontal depth of field is fairly consistent. But imagine the same photo where one of the people in the crowd in the foreground is holding up a banner that takes up half of the right side of the photo. Applying a gradual blur-everything-vertically-away-from-the-middle will mean that the bottom of his banner will be blurred (as it should be because he’s in the foreground and the focal point is somewhere out on the field) but the middle of the banner will be nice and crisp which simply never happens in real miniature photography.
The crux of the matter is, inappropriate use of tilt-shifting is exactly as silly as whapping a lens flare on your cat’s shoulder. Learn from my lens flare crimes. Just because it can be done it doesn’t mean it should be done.