Shutter speed/apertureÞ
depth of field
The choice is between high shutter speed (short exposure) combined with wide aperture, or low shutter speed (long exposure) combined with small aperture. The smaller the aperture (the higher the f number), the longer the depth of field. The photographer will give precedence to one of these settings and the other will follow accordingly.
The major variations entailed by these changes in the exposure (which determine the photographers choice) will be on the rendering of the light effects on the objects.
Subject : waves on the beach at night
In these examples, it is supposed
that the major effect was the contrast between two suggestions
of movement |
Short exposure
(1/250 second) |
Long exposure (1/4 second) |
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Here the emphasis is on the
enveloping night, with tiny light effects in sharp outlines |
The same subject with a longer
exposure time: the emphasis is on the radiating effect of the
reflected moonlight, which gives a soft-focus
effect on the lit areas and lightens the colour of the dark
areas |
The photographer gave priority to the choice of shutter speed |
In this case, the high shutter
speed implied
- a comparatively large aperture
- a fairly small depth of field: the picture is blurred
except on the waves, which focuses attention on them
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Here, the low speed entailed
- a smaller aperture
- a high depth of field: the whole of the sea is clearly
defined
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