Achieving Proper Background Perspective

 In a previous post I mentioned that distorted backgrounds can be a great distraction in glamour composites, drawing the viewer's eye away from the model. Backgrounds need to be more like how our eyes see. Vertical lines need to be vertical, and horizontal lines need to be horizontal.

This is important for indoor composites such as this composite of the wonderful Andrelica:

 Andrelica composited into an image of the Arizona Inn, Tucson, Arizona.

Andrelica composited into an image of the Arizona Inn, Tucson, Arizona.

Indeed, in the above example, the vertical lines (the lamps, the artwork on the back wall, the curtains and side of the piano on the right) are vertical. Likewise, the horizontal lines (top of the piano) are horizontal.

Outdoor glamour composites also benefit from backgrounds in proper perspective, as is this second image of Andrelica:

 Andrelica composited into a dusk scene at Marina Bay, Singapore.

Andrelica composited into a dusk scene at Marina Bay, Singapore.

How distracting it would be if the sides of the skyscrapers in the background were not parallel, and the top of the Fullerton Hotel was not horizontal.

What is the secret to getting backgrounds with perfect perspective? It is simply a matter of keeping the camera sensor perfectly vertical. This presents a second problem: what if you want more foreground at the bottom of the image and cannot back up? Or, what if you want more of the top of a scene in the image? Pointing your camera up or down would cause the distortion we are seeking to avoid. The answer is to use a perspective control lens, also know as a tilt-shift lens:

 The Nikon 45mm perspective control lens shifted upward.

The Nikon 45mm perspective control lens shifted upward.

The camera is mounted on a tripod and positioned perfectly vertically via the use of a small bubble level on the top of the Really Right Stuff ball head. This type of lens allows the photographer to get more foreground in the image by shifting the lens downward. This is great if a full-length glamour composite is envisioned and the model needs a place to stand, as in the second example of Andrelica above. Alternately, the lens can be shifted upward (as shown here) to include more of the top part of a scene in the final image. This is all done with no distortion whatsoever.

These are manual lenses, but are quite easy to use once you are familiar with them. Nikon makes them in three focal lengths: 24mm, 45mm and 85mm. Canon makes four. I much prefer the 45mm lens for shooting backgrounds. The downside is that these lenses are expensive, close to $2,000 each. In my mind, they are totally worth it!