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Shutter Speed

Shutter speed is a measurement of the time the shutter is open, shown in seconds or fractions of a second: 1 s, 1/2 s, 1/4 s … 1/250 s, 1/ 500 s, etc. The faster the shutter speed, the shorter the time the image sensor is exposed to light; the slower the shutter speed, the longer the time the image sensor is exposed to light.

If you are photographing a subject that is in motion, you will get different effects at different shutter speeds. Fast shutter speeds will “freeze” motion, while slow shutter speeds introduce blur from two sources: camera movement (camera shake) and subject. In other words, the faster the shutter speed the easier it is to photograph the subject without blur and “freeze” motion and the smaller the effects of camera shake. In contrast, slower shutter speeds are suited to suggesting the motion, such as that of flowing water or other moving subjects. Changing the shutter speed gives you control over whether to “freeze” or suggest motion.

In the photograph taken at a fast shutter speed, the walker appears “frozen” in mid step. This is due to the fact that only a brief instant of the walker's motion was recorded because the shutter was only open for a short time. In the photograph taken at a slow shutter speed, the walker is blurred. This is due to the fact that the walker moved while the shutter was open.

Fast shutter speed

Slow shutter speed

Fast shutter speeds freeze motion.

Slow shutter speeds suggest motion.

Shutter speeds change as shown below.

Choosing a shutter speed one step faster than the current shutter speed (by, for example, changing shutter speed from 1/60 s to 1/125 s) is referred to as “increasing shutter speed by one step” and halves the amount of time the shutter is open. Choosing a shutter speed one step slower than the current shutter speed (for example, by changing shutter speed from 1/125 s to 1/60 s) is referred to as “slowing shutter speed by one step” and doubles the amount of time the shutter is open.

If you are using a Nikon digital SLR camera, shutter speed changes in 1/3 steps; some models also support increments of 1 step and 1/2 step.

Camera Blur and Motion Blur If the camera or subject moves while the shutter is open, the picture will be blurred. Blur caused by subject movement is referred to as “subject blur” or “motion blur”; blur caused by camera movement (“camera shake”) is referred to as “camera blur.” The results in both cases are similar, but whereas blur caused by subject movement is generally regarded as a legitimate way of expressing motion in photographs, blur caused by camera shake is frequently seen as a flaw. While camera blur does not necessarily render a photograph a failure, caution should be observed to avoid unintentional camera blur. The main subject is in both cases blurred, but the results are distinct from blur caused by the subject being out of focus (focus blur).

Camera blur

The camera moved while the shutter was open, producing blur.

Motion blur

The main subject moved in the wind while the shutter was open and is blurred; the surrounding flowers and leaves, which were at rest while the shutter was open, are not.

Out-of-focus shot (focus blur)

The camera is focused not on the flower in the center but on a flower further back.

Intended result

The central flower is in focus.

camera information display

Shutter speed:

Speeds faster than one second are shown as fractions (e.g.: …1/125, 1/160, 1/200, 1/250…). Some cameras may omit the numerator so that “1/125” becomes “125,” “1/250” becomes “250,” etc. Speeds slower than one second are shown by a double prime symbol following the value (e.g.: 1 ˝).