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Introduction

There are two primary reasons why a view camera would be a better choice for the photographer--image size and swings/shifts/tilts. There is little argument that a large negative or transparency results in sharper, better results--when all else is equal. Smaller film-formats generally mean greater depth of field with minimal diffraction so swings and tilts are rarely needed in 35mm. However, that still means that we need to control shifts.

What is a "Shift" or "Perspective Control Lens"?

A Shift lens or (PC lens) is a lens that is designed to move up and down or left and right in relationship to the film. These lenses are generally wide-angle lenses and use the natural distortion of the lens to control the image. When photographing a building it is important to position the camera body so that it is perfectly in parallel to the building both vertically and horizontally so there will be no "leaning" or distortion of the building in the viewfinder and on film. The principle of keeping the film in alignment with the object is the root of using a shift lens. If you point the camera upwards to frame the building properly, the top of the building starts to lean away and shrink. Unfortunately, a straight ahead shot is rarely the composition needed. You will get lots of street and sidewalk and little building. This is where the shift lens comes in.

If the center of the subject is to be placed in the center of the image, the center of the lens must be directly in alignment with both centers. If you point the camera up at the center of the building, it ends up in the center of your viewfinder. But, by doing so, the film now is no longer in parallel with the building and the unwanted leaning results.

The important thing to remember is that the film must be kept in perfect alignment with the subject. How then do we place the center of the subject in the center of the film? By moving the center of the lens to be exactly in alignment with the other centers. The shift lens does just this.

How do you use a Shift lens?

Typically, you will visualize the final composition prior to starting the shifting process. Place the camera in the location desired and frame the shot like you would with any other lens. This framing and visualization step is important as it is the starting point for proper use of not only a shift lens, but any camera that has swings, tilts and shifts. Although, you can handhold a camera with a shift lens, I highly recommend using a tripod--especially one with bubble levels. Second step is to now align the film with the subject. Most of the time, this means making the film perfectly vertical and the horizontally in line with the subject. (If the building wall is directly facing south, you will have the camera pointed directly north). Now shift (slide) the lens in the direction you had pointed the camera to get the desired composition.

In this picture of the Grand Haven, Michigan channel lights, I desired to keep the catwalk supports vertical and the lights upright. With a normal wide-angle lens, not only did they lean, but the icy seawall wasn't straight. I positioned the camera so that it was perfectly centered on the end of the seawall. By shifting the lens as far to the left as it would go and downward, I achieved this composition.

This schoolhouse was also photographed with the 35mm shift lens. Camera leveled, the center of the image was the corner of the building just above where the bricks meet the basement wall. I then shifted the lens over and up to keep the verticals straight and the side walls proportionally correct.

Hazards of the shift lens

A grid screen is very helpful to aid in the alignment of the verticals. Failure to get the camera perfectly level is a problem as you will tend to get one side vertical, but the other side leaning. Shift lenses rarely provide stop-down linkage with the camera body, so they must be focused wide open and manually stopped down for the picture. A locking button is usually provided so it is an easy matter to focus/compose, press the stop-down button and take your picture.

Another hazard of the shift lens overdoing it. An entire generation has grown up seeing building pictures taken without lens shift. A perfectly aligned building picture is almost unnerving these days. Instead of totally correcting the perspective, you may wish to just control it a bit. Even a 50% reduction in the "lean" will improve the picture without startling the viewer. Over-correction is a guaranteed way of wasting film. Err on the side of under-correction.

Exposures with a shift lens

Some guides recommend getting your exposure prior to shifting the lens. When shooting in manual exposure mode and using a through-the-lens meter this is good advice. The angle of transmitted light being blocked by the mirror causes the image to vignette in the viewfinder. This vignetting is only evidenced in the viewfinder and not on the film, but it is usually severe enough (when using maximum shift) to throw the exposure reading out by as much as two stops. This is a critical problem with those cameras that get their metering solely off the focus screen. Cameras such as the Olympus OM-4(Ti) and OM-2S meter off a sub-mirror in the mirror-box and do not use the finder screen or penteprism at all. I have noticed little exposure shift with these cameras and when placed in auto mode they get their exposures in real-time off the shutter curtain and film surface so exposures are always accurate.

What if I don't own a shift lens?

It isn't necessary to own a shift lens to perform perspective control. Align the camera with the subject the same way described above and use a lens wide enough to include the final composition. The final image is then heavily cropped. This, of course, works better with medium format cameras than 35mm because of the image size, but the rules are still the same.

The creative touch

The following photograph illustrates what happens when you use the shift lens in a manner not typically recommended. I wanted to accentuate the convergence and also capture the tree reflection in the window. Instead of pointing the camera straight ahead, I pointed it up to the sky and shifted the image downward.

(Olympus OM-2S, 35/Shift, Fujichrome 50)