FAMOUS PHOTOGRAPHER: Dorothea Lange
Born: May 26, 1895
Died: October 11, 1965 (aged 70)
Profile: One of the pre-eminent and pioneering documentary photographers of the 20th century.
Known for: Portraits of displaced farmers during the Great Depression.
Quote: “One should really use the camera as though tomorrow you’d be stricken blind.”
The exposure triangle.
A photograph’s exposure, as captured by your camera, determines how light or dark an image will appear. The three fundamental elements of exposure are aperture, shutter speed and ISO, which together make up what we call the exposure triangle.
These three elements form the foundation of successful photography and we will be looking at each, one by one.
Today we will look at shutter speed.
What is shutter speed?
The shutter speed refers to the length of time a camera’s shutter is open for, and subsequently how long the digital sensor (or film) is exposed to light in order to capture the scene.
When you press the shutter release button or use the camera’s self-timer function, the shutter (in the form of blades that block the sensor/film) open and close, allowing light to enter.
Most DSLR cameras use a mechanical shutter, although some current cameras (e.g. mirrorless cameras) use an electronic shutter.
How is shutter speed measured?
Shutter speed is measured in seconds or, in most cases, fractions of seconds (e.g. 1, 1/2, 1/15, 1/125, 1/1000).
The larger the denominator, the faster the speed (i.e. 1/500 is faster than 1/30 which, in turn, is faster than 1/4).
How does shutter speed affect my images?
As is the case with aperture, the shutter speed plays both a technical and creative role.
First, changing the shutter speed alters the amount of light let in to the camera, thereby affecting the overall exposure.
Second, adjusting the shutter speed allows the photographer to either freeze or blur motion.
Which shutter speed should I use?
Choosing which shutter speed to use depends upon many factors.
Following are some questions to ask yourself before you capture a scene/subject:
How much light is available?
How fast is the subject, or the elements in your scene, moving?
How do you want to capture the scene and/or subject?
Do you want to freeze motion or blur it?
Here are some guidelines:
To freeze motion, choose a faster shutter speed.
To blur motion, choose a slower shutter speed.
What is camera shake and how do I avoid it?
Camera shake is when your camera moves while the shutter is open. It results in blurred images, but is not to be confused with unwanted motion blur (when the subject moves) or out of focus images.
To avoid camera shake, choose a shutter speed with a denominator that is larger than the focal length of the lens (photographer’s call this the reciprocal rule).
For example, if you’re shooting with a 50mm lens, use a shutter speed of 1/60 or faster; if your lens 200mm lens, shoot at 1/250 or above.
Does my shutter speed affect the aperture?
Capturing a correct exposure is a balancing act between shutter speed, aperture and ISO. As one increases, one (or both) of the other two settings has to decrease to maintain the same exposure level.
Are there any other cool things can I do by manually controlling the shutter speed?
Here are a few:
Panning is the horizontal movement of a camera as it scans a moving subject. When using a slower-than-normal shutter speed, it results in a relatively sharp subject against a blurred background. Requires practice and patience!
Zoom blur is a technique which you can use to add motion and an abstract feel to your photos. To be used sparingly (if at all)!- Combining a long exposure time (i.e. very slow shutter speed) with multiple pulses from a handheld flash can replicate a multiple exposure effect.
Light painting is a technique which involves moving a hand-held light source while taking a long exposure photograph, either to illuminate a subject or to shine a point of light directly at the camera.
Bulb mode allows the photographer to take a picture for as long as the shutter is depressed and is useful for capturing lightning, star trails, light painting and fireworks.
Handheld vs. tripod.
If you’re using a slow shutter speed (anything slower than 1/60) you will need to either use a tripod or some some type of image stabilisation. More current cameras and lenses come with built-in image stabilisation, so be sure to check.
A tip regarding filters.
Neutral-density (ND) filters are dark grey filters that block the amount of light entering the lens. They are available in a range of different strengths, each enabling the use of progressively slower shutter speeds. Very strong ND filters, combined with small apertures and low ISO sensitivities, enable the use of shutter speeds that stretch for minutes, even in the middle of a clear summer day.