Canon EOS-3 manual Basic Terminology Depth of Field, 102

Basic Terminology 4

●Depth of Field

This is the range in front of and behind the plane of optimum focus where acceptable focus can be achieved. The smaller the aperture (the larger the F-number), the greater the depth of field will be. And the larger the aperture (the smaller the F-number), the shallower the depth of field will be.

The depth of field is affected as described below:

(1)A smaller aperture (a larger F-number) increases the depth of field.

(2)A lens with a shorter focal length increases the depth of field.

... A wide-angle lens obtains a greater depth of field than a telephoto lens.

(3)A longer distance between the camera and subject increases the depth of field.

(4)The depth of field behind the plane of optimum focus is twice as long as the depth of field in front of the plane of optimum focus.

Range of acceptable focus

Point of optimum focus

1

2

Taken with an f/22 aperture. Taken with an f/2 aperture.

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