Wednesday, January 17, 2007

Scheimpflug!

I got a new lens. I'm probably the only person in my entire town who owns this one: the Hartblei 35mm Super-Rotator. It's a medium format tilt-shift lens that rotates 360 degrees, all on independent controls. I got it in a Nikon mount, perfect for a D200. (And it meters through a D200 as well, even though it's completely manual.)

The shift part lets you control perspective when you're shooting something tall, like a building, by moving the lens off-center from the sensor.

The tilt control sets the lens at an angle to the sensor. This creates the Scheimpflug Effect, which states that the film/sensor plane, lens plane, and focus plane will all intersect at a point. (Actually, at a line, because they're planes.) This means that you can change your depth of field and do interesting things with it. For instance...

Normally, setting a lens at f/2.8 and aiming it at an angle would produce a band of focused subject, like this:























When you tilt the lens by a few degrees, it brings the entire plane of the keyboard into focus


























You can go the other way too. If you tilt the right way, you create a plane of focus that is orthogonal to the parallel in front of you. That makes images like the third one here:






























So then. Anyone know how to stick tables into Blogger?

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