8. How to Take Photos 3: Shutter Speed
Almost all this information comes from lessons by Chris Parker & Chris Bray, including the photo examples. The video was made by Ilford Photo.
Every camera has a shutter inside - a little door that opens and closes, exposing either film or a digital sensor to light. Shutter speed is the amount of time in which your film or sensor is exposed to the outside world, and determines how much light hits it. Every program mode on your camera uses different shutter speeds, but if you want to control it yourself, the best program mode is either M for Manual, or TV on a Canon, meaning Time Value (or S on a Nikon, meaning Shutter Speed). S and TV do the same thing - you can choose the shutter speed, and the camera chooses the rest of the settings automatically to get a good exposure.
The biggest problems that shutter speed addresses are under exposure (your photo is too light––often the sky is white)
and over exposure (your photo is too dark).
This can be tricky because, for fast moving subjects, you need a very fast shutter speed, unless you want your subject to be blurry (maybe you do, that's a creative choice). Most landscapes are fairly still, so, unless there's water or it's really windy, slower shutter speeds shouldn't result in motion blur, so long as you use a tripod. For longer exposures, expect moving things to blur away or vanish––for these shots you need to use a tripod, or everything will be blurry.
Long exposures are great for shots of water, to soften it. This can look nice for rivers and waterfalls (NOTE: these kinds of photos usually require an ND filter):
also stars at night:
Note that shutter speed is not the only factor at play in determining motion blur. It also depends on the speed and distance of your target, and the amount of light. So, there's no simple way to tell you which shutter speed to work for people running, or cars going by, or a bird swooping down to a river. You just have to practice different speeds and see what works best.
So, how do you get to creatively change your shutter speed without your photo becoming over or under exposed? The answer is by the balancing effect of aperture and shutter speed working together. So, when one requires less light, you compensate by allowing more light through the other. You need a smaller aperture? Add a longer shutter speed. Choosing a shorter shutter speed? Then make the aperture larger. In this way, you can be creative while getting the right amount of light (this requires trial and error, obviously, but most new digital cameras will indicate if there’s enough light coming in).
Shutter speed is very much a creative choice. A little motion blur really helps sell the idea of things in motion. With a camera, you can take such a fast shutter speed that even really fast moving objects can appear frozen in space – like a helicopter in midair with its rotors frozen:
It looks odd. Slowing the shutter speed to allow for some blur greatly enhances the believability and legibility of what’s going on in the image.
A 6 second shot is good for a camp fire at night to capture all the little embers flying.
With long exposures at night (using a tripod), playing with light is exciting – the camera will record bright lights more than other moving things. So you can carry a flashlight and leave a light trail.
These kinds of shots take about 10 seconds – you can even add a flash at the end for the people.
Burning steel wool on a string looks great too (attach it to a clip so it doesn't go flying and catch something on fire).
Long exposures at night are a great time to use the 10 second delay timer to your shutter button – to avoid camera shake from you pressing the button. Also, turn off the lens stabilizer when it’s on a tripod – as some introduce camera shake when the camera is very steady.
Panning Shots: with long exposures, you can actually pan, or move your body and camera to follow a subject in motion. The effect is that the subject – a car or a runner, animal, etc. is more in focus, while the background blurs. A tenth or twentieth of a second is a good setting for this.
Zooming Shot: with a longer exposure you can also practice zooming in while you take the shot – it creates tons of leading lines.
One common question students have is, what’s the slowest shutter speed you can get away with before having to use a tripod? And the answer is it depends. It depends on what lens you’re using, and how far you’ve zoomed in. The more you zoom in, the more each little shake effects the photo, so for telephoto and macro lenses you generally need to use faster shutter speeds. For wide angle lenses, you can get away with slower shutter speed. A good rule of thumb is this equation:
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