Shutter Speed — Freeze the Moment or Let It Move?
A camera doesn't have to photograph movement the way your eye sees it.
One of the first things photographers learn about shutter speed is that a fast shutter speed freezes movement and a slow shutter speed produces blur.
That is perfectly true.
But it is also rather like saying that a piano has black keys and white keys. It describes what is there without really explaining what you can do with it.
Shutter speed is not simply a technical camera setting.
It is a creative decision about how time should appear in a photograph.
Do I want to freeze a water droplet in mid-air?
Do I want to see every feather on a bird taking flight?
Do I want a racing car to appear completely stationary?
Or would I rather show the sensation of speed, with the car sharp but the background sweeping past in a blur?
The interesting thing is that none of these photographs necessarily represents movement exactly as our eyes perceive it.
The camera can show us moments too brief for us to examine, or it can combine several seconds of movement into a single image.
That makes shutter speed one of the most fascinating controls on a camera.
What Is the Shutter Actually Doing?
At its simplest, the shutter controls how long the camera's sensor is exposed to light.
A shutter speed of:
1/2000 second
is an extremely short exposure.
A shutter speed of:
1/30 second
is much longer.
An exposure of:
2 seconds
allows the camera to collect light and movement for two whole seconds.
That difference can completely transform the appearance of the same scene.
Suppose somebody runs across the garden.
At 1/2000 second, their movement may appear completely frozen.
At 1/250 second, they may still look fairly sharp.
At 1/30 second, their arms and legs may begin to blur.
At 1 second, they may become little more than a ghostly shape crossing the picture.
Nothing about the subject has changed.
Only our decision about how much time the photograph should contain has changed.
A Photograph Is Not Necessarily an Instant
We often describe photographs as capturing an instant.
Sometimes they do.
But a photograph really records everything that happens during the exposure.
With a very fast shutter speed, that period is so short that movement appears frozen.
With a long exposure, the photograph becomes something rather different.
It becomes a record of movement over time.
That is why flowing water can appear silky.
Car headlights become trails of light.
Stars can form arcs across the night sky.
People walking through a scene can become blurred or even disappear altogether.
Photography therefore gives us an unusual ability.
We can decide how much time exists inside a single image.
Experiment 1 — Freeze a Water Droplet
This is one of the easiest and most dramatic shutter-speed experiments.
You need very little equipment.
A tap, dripping bottle or hose can provide the water. A dark or uncluttered background helps considerably.
Start perhaps at:
1/250 second
Then try:
1/500 second
1/1000 second
1/2000 second
or faster if there is enough light.
Compare the photographs.
At the slower speeds, the droplet may stretch into a streak.
As the shutter speed becomes faster, individual droplets become increasingly defined.
At sufficiently high speeds, you may capture shapes that were effectively invisible to your eye.
A splash suddenly becomes a collection of separate droplets, curves and sheets of water.
This is one of the wonderful things about photography.
The camera has not invented anything.
It has simply allowed us to inspect an event that happened too quickly for us to study normally.
Why Fast Shutter Speeds Need Plenty of Light
There is an important consequence.
If the shutter is open for only a tiny fraction of a second, very little light reaches the sensor.
The camera must compensate somehow.
We might:
open the aperture;
increase the ISO;
add more light;
or accept a darker photograph.
This introduces one of the central ideas in photography.
Camera settings do not operate independently.
Change one thing and something else often has to change with it.
Suppose I photograph a water splash at 1/125 second and then change to 1/2000 second.
I have dramatically reduced the amount of light reaching the sensor.
If I want the photograph to remain correctly exposed, I must compensate.
That might mean using a wider aperture, increasing ISO or providing considerably more illumination.
This is why freezing very fast movement indoors can be surprisingly difficult.
The shutter speed may be technically correct for the movement, but there simply may not be enough light.
Experiment 2 — Photograph Something Falling
Another excellent practical experiment requires little more than a ball.
Drop it against a plain background.
Photograph it at a series of shutter speeds.
For example:
1/50 second
1/125 second
1/250 second
1/500 second
1/1000 second
With the slower shutter speeds, the ball becomes elongated.
With faster shutter speeds, it becomes progressively sharper.
You can make the experiment more scientific by keeping the camera, lighting and drop position as consistent as possible.
You could even place a ruler or marked background behind the falling object.
The amount of blur now becomes evidence about how far the object moved during the exposure.
Suddenly photography has become a physics experiment as well.
Sport — Do We Always Want to Freeze Everything?
Sports photography is one of the obvious uses for fast shutter speeds.
A footballer striking a ball, a tennis player serving or a sailor hiking hard in a gust can all benefit from a relatively fast shutter.
But there is a danger.
If everything is frozen perfectly, sometimes the photograph can actually lose its sense of movement.
Imagine a cyclist travelling at considerable speed.
Photograph the cyclist at 1/2000 second and the bicycle may appear to be parked.
The wheels are sharp.
The background is sharp.
Even the rider's clothing may be frozen.
Technically impressive perhaps, but does it actually look fast?
Sometimes a little movement communicates the event better.
A slightly blurred wheel or background can tell the viewer immediately:
this subject was moving.
Wildlife Photography — Where a Fast Shutter Can Reveal the Invisible
Bird photography is another excellent example.
A bird sitting on a branch may require nothing extraordinary.
But once the bird takes flight, the situation changes dramatically.
Wing movement can be extremely fast.
A shutter speed that seemed perfectly adequate for the stationary bird may produce badly blurred wings moments later.
That does not necessarily mean the photograph has failed.
Wing blur can produce a wonderful sense of movement.
But if the aim is to record individual feathers or freeze a bird at the instant its wings are fully extended, a considerably faster shutter may be required.
Again, the creative decision comes first.
Do I want scientific detail?
Or do I want the sensation of flight?
Those are not necessarily the same photograph.
Slow Shutter Speeds — When Blur Becomes the Picture
Camera shake is usually regarded as something to avoid.
Motion blur is often described in the same way.
But blur is not automatically a mistake.
It can be one of the most expressive tools available to a photographer.
Consider a waterfall.
At a fast shutter speed, we see thousands of separate droplets.
At a slower shutter speed, those droplets merge into smooth ribbons of water.
Neither photograph is more truthful than the other.
They simply describe different aspects of the same event.
One shows structure.
The other shows flow.
Experiment 3 — Photograph Flowing Water
A fountain, stream or even water running from a garden hose provides an excellent experiment.
Mount the camera securely if possible.
Take a series of photographs using increasingly slow shutter speeds.
You might try:
1/500 second
1/125 second
1/30 second
1/8 second
1/2 second
1 second
Several seconds
At the fast speeds, droplets and splashes should be clear.
As the exposure length increases, the water will begin to merge.
Eventually it may develop the familiar smooth, silky appearance associated with long-exposure photography.
This is an excellent demonstration because the subject has not changed at all.
Only the way the camera records time has changed.
The Tripod Suddenly Becomes Important
Once shutter speeds become slow, another problem appears.
The photographer moves.
Even tiny movements of the camera during an exposure can soften the photograph.
This is where a tripod stops being an optional accessory and becomes part of the photographic process.
For exposures lasting a second or more, a tripod is normally extremely useful.
A remote shutter release or the camera's self-timer can help too, because pressing the shutter button can itself introduce vibration.
This connects directly with another important lesson in photography:
the best accessory is often not the most exciting one.
A good tripod may improve photographs far more than yet another lens.
Panning — Let the Camera Move
Panning turns the normal rules around.
Instead of trying to keep the camera perfectly still, we deliberately move it.
Imagine photographing a cyclist travelling from left to right.
Rather than pointing the camera at one place and waiting for the cyclist to pass, I follow the cyclist with the camera.
I begin moving before taking the photograph.
I continue moving while pressing the shutter.
And importantly, I continue the movement afterwards.
The result can be spectacular.
If the camera follows the subject successfully, the cyclist remains relatively sharp while the background becomes streaked.
The photograph communicates movement immediately.
Experiment 4 — Learn to Pan
This is a particularly good exercise because it costs nothing and improves with practice.
Find a safe position beside a road, cycle path or other location with predictable moving subjects.
Begin perhaps with:
1/250 second
Then try:
1/125 second
1/60 second
1/30 second
As shutter speed decreases, the effect becomes stronger but the difficulty increases.
At 1/250 second, you may achieve plenty of sharp photographs but relatively little background blur.
At 1/60 second, the impression of movement may be much stronger.
At 1/30 second, a successful photograph can look superb, but many frames may fail.
That is not a problem.
Photography is often about experimentation.
The failures teach us what our technique can and cannot yet achieve.
The Secret of Panning Is Follow-Through
People often press the shutter and immediately stop moving the camera.
That usually produces poor results.
Think of panning rather like swinging a golf club or tennis racket.
The movement should continue smoothly through the exposure.
Track the subject.
Match its movement.
Press the shutter.
Keep turning.
The smoother the movement, the better the chance of obtaining a sharp subject against a blurred background.
Burst shooting can help, but technique matters more than simply taking hundreds of photographs.
Experiment 5 — Photograph a Spinning Wheel
A bicycle wheel gives another interesting demonstration.
Place the bicycle securely so the wheel can be spun safely.
Photograph it at different shutter speeds.
At a high shutter speed, individual spokes can be frozen.
At slower speeds they begin to merge into arcs.
At still slower speeds the wheel may look almost transparent.
This produces an important question:
Which photograph looks most like a wheel that is spinning?
Curiously, the technically sharpest image may communicate the least movement.
Intentional Camera Movement
We can take the idea even further.
What happens if we deliberately move the camera during a longer exposure?
Instead of following a moving subject, move the camera itself.
Try photographing trees using perhaps 1/4 second or 1/2 second while moving the camera vertically.
The trunks can become long abstract streaks.
Move horizontally and the whole scene changes again.
This technique is commonly called intentional camera movement.
It sits somewhere between conventional photography and painting.
The camera still records the real world, but movement transforms it.
Whether somebody likes the result is of course subjective.
But as an experiment it teaches an important lesson:
blur does not have to mean failure.
What About Image Stabilisation?
Modern cameras and lenses can make handheld photography at slower shutter speeds much easier.
Image stabilisation can compensate for camera movement.
But there is an important distinction.
Stabilisation can help compensate for the camera moving.
It cannot normally stop the subject moving.
If I photograph a completely still building using a slow shutter speed, image stabilisation may help enormously.
If I photograph a running dog using the same shutter speed, the camera may be perfectly stable while the dog is badly blurred.
That distinction is easy to forget.
Shutter Priority — A Useful Mode to Explore
Many cameras offer a mode in which the photographer chooses the shutter speed and the camera selects an appropriate aperture.
On Canon cameras this is usually marked Tv.
Other manufacturers may use S.
For practising shutter-speed photography, this can be extremely useful.
Choose the shutter speed according to the visual result you want and allow the camera to deal initially with aperture.
It makes an excellent step between fully automatic photography and complete manual control.
Eventually, of course, photographers may want to control aperture, shutter speed and ISO together.
But there is nothing wrong with allowing some automation when it helps concentrate attention on the thing being learned.
A Simple Shutter-Speed Challenge
Here is an experiment anyone with a camera can try.
Photograph five subjects:
Water splashing.
A moving car or bicycle.
Someone walking or running.
Flowing water.
Something spinning.
For each subject, take photographs at several shutter speeds.
Do not simply ask:
"Which photograph is sharpest?"
Instead ask:
Which photograph tells the story of the movement best?
That is a much more interesting photographic question.
Fast Is Not Better Than Slow
One of the traps when learning photography is to think in terms of technically better settings.
Fast shutter speeds are not inherently better than slow ones.
Nor are sharp photographs automatically better than blurred ones.
Everything depends upon what the photographer is trying to communicate.
A kingfisher entering the water might look extraordinary frozen at 1/4000 second.
A waterfall may look beautiful photographed for several seconds.
A racing car can appear dramatically fast when panned at 1/60 second.
Each image uses shutter speed for a different purpose.
The Camera Allows Us to See Time Differently
This is what makes shutter speed so much more interesting than a number on a camera display.
It changes our relationship with time.
Photography can show us:
a fraction of a second that our eyes could never properly examine;
several seconds compressed into one image;
motion transformed into blur;
movement apparently stopped completely;
or a moving subject isolated against a sweeping background.
The camera therefore does something rather extraordinary.
It does not simply photograph what something looks like.
It can photograph how something moves.
Conclusion — Decide What You Want Movement to Look Like
When learning photography, it is tempting to search for the "correct" shutter speed.
There often isn't one.
There is simply a shutter speed appropriate to the photograph you are trying to make.
Before changing the dial, ask yourself a much better question:
Do I want to freeze this movement, or do I want the viewer to feel it?
Sometimes the answer will be 1/2000 second.
Sometimes it will be 1/30 second.
Sometimes it may be several seconds.
And sometimes the most interesting photograph will contain deliberate blur.
That is the real creative power of shutter speed.
A camera doesn't have to photograph movement the way your eye sees it. It can stop time, stretch it, or turn it into part of the picture.
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