APERTURE CONTROL

The size of the aperture (lens opening) determines the depth-of-field of the final image as well as the intensity of the light falling on the film. Depth-of-field is the range in front of and behind the subject that appears sharp in the final image. Depth of field increases as the focal length decreases. The wide angle position of the lens will have a greater depth of field at a given aperture than at the telephoto position.

Large

f/3.5

f/4

f/5.6

f/8

f/11

f/16

Small

 

 

 

 

 

 

SHUTTER CONTROL

In addition to controlling the duration of the exposure, shutter speeds determine how moving subjects will appear in the final image. Use a fast shutter speed to stop the motion of your subject, use a slow shutter speed to blur the motion.

Large Aperture

(small f-number)

Range in focus is narrower.

Large apertures (small f-numbers)

Small Aperture

(large f-number)

Range in focus is deeper.

Small apertures (large f-numbers)

30s 6s 1s 1/8s 1/45s 1/125s 1/250s 1/2000s

Slow

 

 

Fast

 

 

Slow Shutter Speed

Fast Shutter Speed

limit the depth-of-field to a narrow range in front of and behind the point of focus. Set a larger aperture when photographing portraits to make your subject stand out from the background.

provide greater depth-of-field. Set a small aperture when photographing landscapes to ensure your entire scene is sharp.

Slow shutter speeds will make a moving subject appear to flow, creating a feeling of motion.

Fast shutter speeds can stop the action and also help prevent blurring caused by camera movement during exposure, known as camera shake.

•Usable apertures will depend on the aperture range of the lens you are using.

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