Technology: Photographs of Architecture and Historic Buildingsby Jeff DeanWisconsin State Historic Preservation Officer (Ret'd.)
There are a couple of ways to do this. With a film camera you must keep the film plane vertical with a special shifting lens that brings into view the top of the building. This is the best way to do this with a digital camera as well, but similar corrections can be made with digital image editing software on a computer, a technique unavailable when using film cameras. However, this will most likely result in the loss of some detail and contrast. The photo above was taken with a 35mm film camera and a 28mm shift, or PC (for perspective control), lens.
“PC” This is short for “Perspective Control.” "Shift" the optical axis of the lens away from the center of the frame, allowing photos to be framed anywhere in the image circle. It can be used to reduce the effects of perspective when photographing buildings from low angles or to change the composition without angling or moving the camera. "Tilt" The optical axis of the lens is normally perpendicular to the focal plane. "Tilt" deliberately angles the optical axis so that objects at different distances from the camera can be kept in focus without stopping down aperture, reducing depth of field and ensuring that the background remains blurred. The first 35mm-format perspective control (PC) lens to correct for perspective distortion to come on the market was the 35mm f/3.5 PC-Nikkor, of 1962. In the images below you see 28mm Nikkor shift lens on a 35mm film SLR (single-lens reflex) camera on the left and a 35mm shift lens on the right on an older Nikon film SLR. The lenses are shifted upward to simulate how they would be used to bring in the top of buildings while keeping film or sensor planes vertical. These lenses operate only in the manual mode, meaning advanced SLRs, whether digital or film, must be set to manual. Exposures must be set with these lenses centered and shifts applied only after exposures are determined.
Several lens manufacturers other than Nikon produce their own versions of PC, shift, and tilt-shift lenses. Two examples below are the 75mm Pentax-Shift lens for a 6x7 cm medium-format SLR, left, and the impressive Olympus 24mm Zuiko-Shift lens for a 35mm SLR. The above lenses have been around for some time. Recently, 28mm lenses have been inadequate for some architectural photography, and manufacturers like Nikon and Canon are producing more advanced tilt-and-shift lenses in the wider focal lengths with electromagnetic apertures. The latest examples of these lenses are shown below. On the left, below, introduced in 2008 by Nikon, is its PC-E Nikkor 24mm f3.5D ED lens, which shifts up to 11.5 millimeters and tilts up to 8.5 degrees. On the right, below, is the PC Nikkor 19mm f/4E ED Tilt-Shift Lens, introduced in 2016.
Canon has introduced two new lenses with 24mm (left below) and 17mm (right below) focal lengths. They are less expensive than their Nikon counterparts.
Click here for the Manual for the 1963 PC-Nikkor f/3.5 lens Click here for the 24mm PC-Nikkor Manual Ken Rockwell: Nikon 24mm PC-E (2008) Click here for a 19mm PC-Nikkor review Click here for Nikon's 19mm PC-Nikkor info Click here for Canon's TS-E 24mm f/3.5L tilt-shift lens Click here for Canon's TS-E 17mm f/4L tilt-shift lens
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