Tall buildings

A tall building photographed from ground level, using an extreme rising shift to retain perfect verticals in the subject, can appear top-heavy with verticals apparently diverging (as shown in Figure 3.6). The reason for this is that the outermost part of the field of view actually becomes elongated owing to geometrical distortion in the image when subjected to extreme shift movements. Therefore, tall buildings are most effectively shot from a vantage point approximately one-third the height of the building being photographed (Figure 9.2). Too high a vantage point will diminish the stature of the building, so to photograph it from one-third

Figure 9.2 A tall building is most effectively photographed from a position approximately one-third of its height, to avoid the problem of geometrical distortion in the image as a result of an extreme rising shift movement.This building was shot from the first floor of a hotel opposite. Access for such shots can present a serious problem

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Figure 9.2 A tall building is most effectively photographed from a position approximately one-third of its height, to avoid the problem of geometrical distortion in the image as a result of an extreme rising shift movement.This building was shot from the first floor of a hotel opposite. Access for such shots can present a serious problem

of its height produces an image with reasonable perspective that also retains its stature. Where it is impossible to find a suitable vantage point above ground level, the most effective solution is to tilt the camera slightly and use less of the shift movement, even though this contradicts the basic theory of architectural photography to retain parallel verticals at all costs.

The best way to do this is to start by tilting the whole camera to include the full height of the building, as with a fixed plane camera. Then correct the converging lines by tilting the lens and image standards to a vertical position. This has the added advantages of both overcoming shift restrictions when using long bellows extensions and keeps both standards close to the rails for optimum stability. A rule of thumb when photographing tall buildings is that when the standards need to be tilted more than 20° to restore their verticality, some under-correction is likely to improve the image. A suggested guide is that the rear image standard should be tilted off vertical again by half the tilt over 20°. For example, if the standards need to be tilted 30° to restore perfect verticality, the rear standard should be tilted back to 25°, 5° off vertical (30° - 20° = 10°; 10/2 = 5°).

Tilting the camera slightly, or choosing a vantage point above ground level, not only enhances the perspective of the building in the image but also overcomes the use of an excessive rising shift movement to include its full height in the picture. Apart from the potential problem of geometrical distortion when using extreme shift movements, the more serious problem of excessive shift is that of vignetting: the situation when the shifted image reaches the outer limits of the circle of illumination causing the corners of the image to blur into a dark vignette. There are, however, other solutions to this problem. If space permits, you could move further away from the building to decrease the size of the building in the image. If that is impractical you could select a wider lens that will have the effect of reducing the building size without changing the perspective as long as the camera position remains the same.

It is also possible to overcome the problem of vignetting by using a little backwards tilt on the front of the camera to move the centre of the image circle down towards the centre of the film area. However, this will cause the top and bottom of the image to go out of focus because of a shift in the plane of focus. To counteract this, you can stop down the lens

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further to increase the depth of field in the image. A final alternative solution if prints are to be the end product of the shoot, is to shade the vignetted corners when printing.

A further problem with tall buildings in confined city streets is the difference in brightness between the top and bottom of the building. This is not a problem if direct sunshine fully illuminates the whole building, but presents a serious problem when the top portion of the building is in bright sunshine, and the bottom of the building is in deep shadow. The problem is likely to be most apparent in the winter months when the sun is lower in the sky. A graduated neutral density filter can reduce the effect to an extent (see Figure 5.2), though never completely. A graduated neutral density filter is most useful in hazy or overcast conditions when the top of a city building can still be over a stop brighter than at the bottom. Because the transition from brighter to darker is gradual (rather than abrupt in direct sunlight), a graduated neutral density filter can be subtly employed to redress this balance.

Finally, if a suitable vantage point is difficult to locate within a confined city area, look around for suitable tall blocks that can be viewed from one-third of the way up the building itself. It should be clear as to which of these blocks are likely to offer a vantage point with an unobstructed view of the building within its cityscape.

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