The shutter inside a camera (in conjunction with other settings such as ISO and aperture) regulates the amount of light that reaches the sensor.

Shutter speeds on most SLRs range from an incredibly short (fast) 1/4000s to as much as 30 seconds.

Fast shutter speeds will freeze motion. Just how fast a speed is required will vary based upon variables that are outlined in the table below.

If a race car is travelling at 100mph it obviously needs a faster shutter speed to freeze it than if it was travelling atis 40mph.

The speed of the racecar is only one of the factors. Other factors which affect shutter speed are:

- focal length of the lens you're using

- the direction that the car is moving in relation to the camera

- your desire to blur the background

- how far away from the car you are positioned

Freezing motion is not always your main purpose. A racecar pictured against a background that is blurred due to motion is much more pleasing than a racecar that looks like it could be setting still on the track.

Another time that you do not want to freeze motion would be the case of photographing a waterfall or fountain area freezing individual drops of water will give the fountain or waterfall and unnatural look. Some photographers will photograph moving water at very very low shutter speeds, while using a tripod. So that the water appears to be moving in the surrounding objects are sharp.

The longer the telephoto lens that you are using a more the image will be affected by the movement of the camera. A shorter lens, such as a 50 mm, can be handheld at a much slower shutter speed than say a 300 mm telephoto.

If you are using a lens that has image stabilization built-in, often called IS, you may be able to shoot at speeds at 1/2 or less of the normal speed you would use. Keep in mind that IS only helps reduce your movement.

Faster shutter speeds allow less light to reach the camera's sensor. This requires more light, a higher ISO, or wider apertures to compensate. Understanding which of these to adjust is part of the learning process. (See Exposure.)

No one guide will give you all the answers that you need. There are many variables such as distance to subject, the speed of the subject itself, how steady you are holding the camera, and the focal length of the lens that you are using. This table will give you some general guidelines to consider when picking the best shutter speed.

Column 1 is for photographing subjects that are moving towards the camera.

Column 2 is for subject that is moving obliquely to or from the camera position.

Column 3 is for objects moving directly across the field of view. Always keep in mind that for this type of photos. You can use panning to help improve the overall image and reduce the required shutter speed. Panning is where the camera follows the subject and you match the subjects speed as closely as you can in the viewfinder.

Note that these table values assume an average distance from camera to subject the 25 feet was used as the baseline. See the notes below, for additional considerations. When that distance changes.

 

1

2

3

Pedestrians (3 miles per hour)

1/30

1/60

1/90

Pedestrians (4 miles per hour)

1/40

1/80

1/120
Children 1/125 1/180 1/250

Vehicles (6 miles per hour)........

1/60

1/120

1/180

Cyclists and trotting horses ........

1/160

1/300

1/500

Foot races and sports ............

1/320

1/600

1/800

Cycle races, horse galloping ......

1/300

1/750

1/900

Trains (30 miles per hour) at 50 ft.

1/150

1/300

1/450

Trains (60 miles per hour) at 50 ft.

1/300

1/600

1/900

At 50 ft. the exposure may be double that at 25 ft.
At 100 ft. the exposure may be double that at 50 ft.