Monday, 24 March 2014

The Need For Camera Movements in Architectural Photography

The single most important requirement in architectural photography is to reproduce straight lines straight. Reproducing straight lines of a building with absolute precision however requires the use of some camera movements which most beginners would not be very familiar with. So we will discuss some camera movements which were possible with view cameras and how they helped keep straight lines straight in various situations. Once we familiarize ourselves with the different camera movements and how they impact the scene in front of us or how the camera captures the scene, we will look into ways to achieve the same with our modern DSLR cameras through the use of some specialist equipment.

view camera movements
view camera movements

DSLR cameras have an image sensor which is mounted parallel with the lens precisely centered on its axis. This is critical as it produces the most optically accurate reproduction of the subject in front of the lens. However there is one catch, in this setup the camera reproduces a true scale only as long as the subject plane remains parallel to the sensor plane. And you will observe the verticals in an image converging as soon as the sensor and subject plane deviates from a perfectly parallel orientation.

For example.

Consider the example of photographing the exterior of a tall building, on many occasions we need to tilt the camera up in order to take in the full height of the building and when we do this we no longer have the sensor and subject planes parallel to each other. The lower part of the building is now closer to the camera than the upper; this varies the scale of reproduction across the subject image. The affect of this on the image will be that the building appears to be falling backwards if we photograph it straight on and it appears to be falling on itself if we photograph it from an angle.

Keeping Sensor Plane and Subject Plane Parallel

We have seen that converging verticals occur when the subject and sensor plane are not parallel to each other. And we do need to include the whole building in our frame; let us now consider our options. To capture the entire building without tilting the camera we basically have four options.

1. Shoot from Further Back

If the location allows, you could move further away from the building so as to include the whole of it without tilting the camera up. This option is however not applicable 90% of the times as we more often than not work in clustered environments with very little space to move. Even if we are able to do it, the shot will have excessive amount of foreground that need to be cropped, making us lose image resolution.

2. Use a Still Wider Lens

It is possible to capture the entire building without tilting the camera up by using a wider angle lens which will cover the entire height of the building without any tilt. However this forces the photographer to use wider angle lenses than necessary and this will affect the perspective of the image, not to mention the excessive amount of foreground that will be captured and need to crop out effectively reducing the image quality and resolution.

3. Raise the Height of the Camera

If you could somehow raise the height of the camera to half the height of the building being photographed, you could capture the building without any tilting the camera up or down. This option could work in some cases as there might be some accessible building directly opposite of sufficient height or you can use a hydraulic platform to shoot from.

4. Move the lens vertically in Relation to the Sensor

This is our final and more practical option, moving the lens in vertically in relation to the sensor; this is called shift movement and it is one of the more important camera movements for architectural photography. In the next article we will discuss the various types of camera movements in detail. 

Related Reading

  1. Architecture Photography Tips - Practical Lens Testing
  2. Lens Distortion
  3. Lens Aberrations
  4. Choosing Lens for Architectural Photography – Aperture, Speed and Performance
  5. Architecture Photography Tips