Chapter Five

CAMERA MOVEMENTS

The view camera generally has four basic movements or adjustments: the rise and fall, the shift, the tilt, and the swing. These adjustments allow the lensboard and the groundglass to be realigned independently of each other. They can be moved up and down, and from side to side; the vertical movement is called a rise and fall, and the horizontal movement is called a shift. When the lens is pivoted around its optical center, it is said to either tilt (up and down on the horizontal axis) or swing (from side to side on the vertical axis). The rear tilt and swing of the groundglass is identical. Not all view cameras are capable of all four movements; some Hat-bed cameras do not offer rise and fall for the lensboard and very few of the bed cameras have rise and fall on the rear standard. Most monorail cameras have all of the movements. However, there are ways to compensate for these limitations by using the till and swing.

The rise and fall and the shift adjustments move the optical center of the lens and the center of the image circle away from the center of the film; consequently, they change the part of the image circle that is recorded on film. Tilting the front of the camera moves the center of the image circle above or below the center of the film, and swinging it moves the center of the image circle to the left or the right of the center of the film. However, the tilt and the swing don't change what section of the image circle is recorded on film since the optical center of the lens and the center of the film stay aligned.

Both the rear tilt and the rear swing adjustments keep the center of the film, the center of the image circle, and the optical center of the film in alignment, so there is no change in what part of the image circle is recorded on film. Instead, with these movements the shapes and sizes of the objects in the scene are altered on the groundglass as parts of it move closer to the lens and parts of it move farther away from the lens.

The rear tilt and swing adjustments are primarily used to alter perspective by manipulating shapes and sizes. Although they don't change the depth of field, these movements can also be employed to bring more of a scene into sharp focus by taking advantage of the Scheimpflug Rule. This secondary function is especially useful when working with a lens of limited covering power, as long as the resulting change in perspective is not objectionable.

The primary purpose of the front tilt and swing adjustments is to aid in focusing and to make use of the Scheimpflug Rule (discussed in chapter 4) without distorting the shape of the objects in the scene. The shapes and sizes of these objects don't change with the front tilt and swing because the distance from the center of the lens to the various sections of the film area remains the same, instead, these tilt and swing adjustments are used to change the plane of focus so it becomes more aligned with the principal plane of the subject. The tilt and swing of the front are also used to return the image to sharp focus if alterations in the perspective have been made by tilt- and swing-adjustments on the back of the camera.

When all camera adjustments are in a neutral position, the center of the image circle, the optical center of the lens, and the center of the film area all line up together. The film area should fit completely inside the image circle; therefore, the size of the image circle projected by the lens must exceed the diagonal measurements of the film. If the image circle is barely large enough to cover the film area, only the rear tilt and swing movements will be useful. Always begin by positioning the camera's adjustments in neutral, and be sure that you're using a lens with an adequate angle of coverage.

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