December 17, 2008

Tilt-shift photography meme

John Nack has been posting items about Tilt-shift photography for a couple of years, and the meme has been hitting strong lately with application of the technique in video. Tilt-shift photography's miniturized scale model look and stop-motion feel is right at the point of cliché -- there's even a new iPhone app that creates tilt-shift photos which was reported today at Wired.

Smashing Magazine's 50 Beautiful Examples Of Tilt-Shift Photography is the definitive survey of photos and video from a Flickr pool and elsewhere.

The New York Times has had a few items too, including a talking slideshow by Vincent Laforet (see picture at left), who has already moved on famously to DSLR video using the Canon 5D MKII. Others posting a stream of items on the trend include Wired and Boing Boing.

There's also a number of articles on Faking tilt-shift with Photoshop (the real thing even with a Lensbaby is not cheap). The basic approach is simple and can be done easily in After Effect or Premiere:
  • Select picture with somewhat elevated viewpoint
  • Blur outside focal area with filters like Lens Blur or Compound Blur with mask or gradient (you'll need a soft touch on your gradient)
  • Increase contrast & saturation, then maybe sharpen
  • Adjust frame rate for a stop-motion look
Here are some other articles that discuss their method:

01/06/09:adds a comment on the AE-List, "Trouble with a mask approach is that, while the blur looks good at the edge and the sharp area stays sharp, the intermediate blur is a cross-dissolved composite of blurred and non-blurred which looks "unnatural", especially at large blur amounts.

I prefer using the "Depth Map Layer" in Lens Blur, which uses a separate gradient layer to modulate the blur effect based on pixel value. You'll have to fiddle a bit with focal distance and iris radius, but you can get a convincing Tilt-shift with this approach.

Compound Blur can do the same thing and renders more quickly, but without the ability to repeat edge pixels, and the blur is a slightly-less natural gaussian style, rather than the more accurate lens blur. If you use a ramp to create your gradient, make sure to precompose the effect or the blur filters won't see it."

In the same thread, Trish Meyer added a tip for changing the frame rate: "you'll render faster by putting the original movie in a precomp, lowering the frame rate, and turning on the Preserve Frame Frame option in Comp Settings Advanced."

Update 2: see Michael Vitti on selective focus in Comments.

Update 3: It seems like the tilt-shift photgraphy and tilt-shift-faking pages at Wikipedia have improved. Also, Keith Loutit has a Vimeo channel with some good examples that shouldn't be overlooked; below is Helpless:

1 comment:

Anonymous said...

If you cannot accomplish this selective focus optically, Sapphire also has an excellent plugin for AE, Combustion and FCP called Convolve Comp which uses a 'kernel' to map focus, very similarly to Brian M's approach. There is a slight difference in the blur gradations (and distortion) between front blur and DoF and DoF to back blur.