Focus
Perhaps
one of the most clearly identified syntactical aspects of photography
is focus. Before the camera obscura that used a lens, this idea was not clearly identified, but today
focus is something that any audience associates with lenses and photography. They understand when a subject in an image is in sharp focus or when
it is out of focus, they also understand how focus can describe distance,
and space between objects, how it can direct the viewer to the area
of interest in an image.
Areas
of sharp focus generally direct the audience to concentrate on that
particular part of the image. Different ideas have evolved about the
use of focus in photography and while these philosophies have sometimes
contradicted each other, each is a tool that can be used with fairly
predictable effects.
With food photographs – you will often notice how the photographer uses selective or differential focus where the food is in focus but the background falls out of focus – as well as placing the focus on the food it also suggests a sense of heat and that the food is hot -
Its similar to how areas fall out of focus through the heat of a fire or a desert on a hot day -
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Image 1
In this image shot on
f4 the point of focus is on the front left bun - note the angel is looking down onto the buns which puts them more on a single plane than images 3 &4 of the sequence -
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Image 2
Shot on f1.4 there is far less depth of field and the bun in the foreground is sharp will those in the background fall off - see how this suggests a sense of warmth and heat. |
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Image 3
In this image shot on f5.6 all the buns are relatively sharp -
not how the camera angle has been altered to a lower angle - shooting more across the buns - as well as creating a greater sense of depth - the position creates a greater physical distance. |
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Image 4
So when we use f1.4 and focus on the bun in the foreground the other buns fall well out of focus. So although the buns are stone cold there is the suggestion of freshness and warmth. |
This image of the road has been shot with a compact camera with the lens wide open - the image has an over all sharpness but the eye is not directed to any particular element through sharp focus - |
In this image of of the same road where the viewpoint has been changed to a lower angle - the focus is on the group of stones in the foreground.
This creates a sense of visual tension that suggests that the stones are an important element of the image.
- notice also how the perspective alters - |
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In the image of the parrot - the even toned background falls completely out of focus |
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However although the background in this image is out of focus we still have a sense of the atmosphere behind the musician. |
What is depth of field?
