The simplest way to do this is to choose a small Aperture setting (a large number) as the smaller your aperture the greater the depth of field in your shots.

最简单的办法是选用最小的光圈设定（镜头上显示的最大的数字），光圈越小，你所获得照片的景深就会越大。

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Portrait mode chooses a large aperture (a small 'f' number) which will make the depth of field (the amount of your shot in focus) smaller.

人像模式用一个大光圈(f值小)，而让景深(清晰对焦的那部分)变小。

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The f-stop, otherwise known as the aperture, determines your depth of field (the area in focus) and how much light can pass through the lens to reach the sensor.

f制光圈(或称光圈)决定相机的景深(对焦区域)以及有多少光能通过镜头到达传感器。

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In addition to daily use as a "pan-focus" lens featuring a wide angle, fixed f8 aperture and shallow depth of field, it is compatible with manual focusing using a lever and capable of close-up shooting as close as 30 cm.

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Shooting wide open, using aperture f2.8 on most lenses, gives you a shallow depth of field that emphasizes the part of the images you are focused on.

CNN: photojournalists share their tricks

Stopping down, using a smaller aperture like f11, or f16, will give you a maximum depth of field, which can help to show a wider scene like devastation from a tornado.

CNN: photojournalists share their tricks