Nikon Perspective Control Camera Lenses

Nikon Perspective Control Camera Lens

Photographs display images similar to those seen by the human eye. They depict distorted distances and make parallel lines seem to connect. Nikon Perspective Control, or PC, lenses correct distortion, and they increase the sharp focus area of photos outward to the edges.

Nikon uses the PC label to describe their line of tilt-shift lenses. A camera is like the human eye in terms of visual perspective and can make things look closer or farther away than they actually are. The PC can correct that distortion and provide clarity and depth of field. These lenses add tilt and shift to the focus position settings. The tilt-shift movement enlarges the focus area, extending it out to the edges of the photo.

The keystone effect in photos occurs when parallel lines seem to converge rather than stay apart. This distortion occurs if the camera is not perfectly level. Camera lenses register distance like the human eye. If the bottom and top of a building are the same distance from the sensors, then the system portrays the top of the building as being farther away. This is the classic photographic distortion effect. It is a common phenomenon when using simple cameras and regular focusing.

A PC makes an adjustment between the lens and the focus sensor to account for distortion. This type of lens can tilt up or down and shift from left to right. The PC technology changes the angle between the lens and focus plane so that the focusing system can overcome the photographic bias of distance, light, and shadow. The tilt changes the perspective of the top and bottom of the image so that the top no longer seems farther away. The shift expands the focus circle outward towards the edges so that the ends of the image do not fade out of focus or seem farther away than they should.

The PC focusing settings let the photographer manually change the angle between the focal plane and the focusing sensors. The photographer can control the angle of the photograph by shifting to the left and right or tilting up and down. The adjustment corrects distortion, and it also increases the depth of field when using a wide aperture setting. The tilt-shift feature enhances landscape photographs and is a useful feature for architectural photography.

The visual correction that occurs with tilt-shift adjustment requires manual focus. Autofocus systems do not work with the bias that PC lenses add to the focusing sensors. The photographer can use tilt or shift separately or combine them for creative photography. The manual adjustments can create miniature effects and enhance many types of photographs.