Tilt-shift Lens
A lens that can be tilted or shifted relative to the sensor, controlling the plane of focus and correcting converging verticals.
Formula / rule
Scheimpflug: subject, lens and film planes meet on a line
Measured in
degrees, mm
In depth
Shifting moves the lens parallel to the sensor, using an oversized image circle to include the top of a building without tilting the camera up — so verticals stay vertical. Tilting swings the plane of sharp focus away from parallel, allowing a receding table top or a whole landscape to be sharp at a moderate aperture. Both movements come from the view camera and are the reason architectural photographers still use them.
Examples in practice
A 24 mm tilt-shift shifted 8 mm upward photographs a cathedral façade with perfectly parallel columns.