What is Shutter Speed?
Shutter speed is one of the fundamental elements of exposure in photography. It’s also the one that’s likely to have the biggest impact on your photographs in the short term.
In fact, we’d go so far as to say that shutter speed has the greatest potential to make or break your photos while you’re learning photography.
If your shutter speed is wrong, your photos could be, well, pretty terrible. That’s why understanding shutter speed is so important.
So let’s start with a basic explanation of what shutter speed means and what effect it has on your photos.
What is shutter speed?
Shutter speed in photography is the duration that the camera’s shutter is open, exposing its film or digital sensor to light, while taking a photograph.
What that means in layman’s terms is that when you press the shutter on a camera, shutter speed is the amount of time that the shutter remains open.
The click you hear is often two clicks: one for when the shutter opens, and one for when it closes. More often than not, it happens so quickly, it sounds like one click.
All cameras work on the principle of a shutter in some form, regardless of whether they have a physical shutter or not.
They either have a physical shutter that moves, as seen on many cameras with interchangeable lenses, or an electronic shutter as we see on phones.
In the case of physical shutters, when you press the shutter release button on top of the camera, the shutter opens, exposing the film or digital sensor, and then closes again.
Depending on whether you are shooting with a DSLR or not, you may also have the mirror move out of the way in the process.
The following video from The Slow Mo Guys shows a camera shutter in slow motion:
In the case of an electronic shutter, the shutter is simply an electronic on/off switch telling the sensor when to read the light and when to stop.
How is shutter speed measured?
Because the shutter is only open for a fraction of time (most of the time), shutter speed is measured in seconds or fractions of a second.
Anything more than a second is often referred to as “long exposure” because of the amount of time the shutter is open.
When you see a number like 1/100 or 1/8, it’s referring to the fraction “one hundredth of a second” or “one eighth of a second” that the shutter is open.
In some cases, it may be shown on your camera as something like 125, 250 or 1000. This is essentially the same thing, without the 1/ in front.
Why do we need shutter speed?
Shutter speed is similar to watching a video. If the shutter is open for an extended period of time (what you’d call a ‘slow shutter speed’), whatever movement occurs will be visible in the image.
If the shutter is open for a short period Guide to Slow Shutter Speed Photographyof time (i.e., a fast shutter speed), very little movement will be shown.
The problem with a photograph is that when you have movement, it creates a blur on the picture that often makes it look muddy or unsharp.
The image below shows an example of a car moving at 100km/h along with various times and how far the car would travel in that period of time.
It represents a view of what the sensor would see depending on how long the shutter is open for.
At the top, we have 1/1000th of a second, in which time the car would not have traveled far.
Thus, if you took an image at 1/1000th of a second, the car would be frozen as if it was not moving at all, as shown below.
At 1/100th of a second, the car hasn’t moved very far, but it would still be moving fast enough for it to cause some blurring in the image as shown below.
At 1/10th of a second, the car has moved halfway across the frame, so blurring would be substantial.
At 1/10th of a second, even holding the camera still for a non-moving object can be challenging because even a small tremor in your hands will cause visible camera shake in the image.
At a slower shutter speed of 1/5th of a second, the car is very blurred as it has traveled the entire way across the frame.
Why don’t we just leave it at 1/1000?
There are three possible reasons why we wouldn’t want to just stick to a faster shutter speed:
- There’s not enough light available to get a good exposure
- Motion blur is being used artistically to create the perception of motion in a photograph
- Sometimes 1/1000 isn’t actually fast enough
Covering the first point, if we wanted to take a photo at 1/1000th of a second, there has to be enough light available to leave the photograph correctly exposed.
Obviously a faster shutter will let in less light – so while your exposure at 1/1000 may be fine outdoors on a sunny day, indoors could be a different story.
That leaves us in a position where sometimes we want to freeze action in low light and we have to rely on a ‘wide-open aperture’ and high ISO to help.
Both of those have impacts on the image, the latter causing grainy images referred to as digital noise.
The second reason is that sometimes we actually want blur. Blur creates the perception of motion and adds to an image, but like anything artistic, it has to be done in the right way.
Panning is one way that slow shutter speeds are used to create the perception of motion.
With panning, we move the camera in the same line as the moving object, from left to right or right to left. This results in the blurred background and a sharp (if you did it correctly) subject.
In the example above, you also get the added value of blurring on the rotating wheels, which shows the cyclist is moving.
What is the recommended shutter speed to use?
Unfortunately, there is no one-size-fits-all – that is part of the challenge of photography and the learning process.
That said, there is one general rule that you should not break in your learning stages and that is the rule of minimum shutter speed.
This rule is to protect you against camera shake, which is natural with most people. The rule is this: Never shoot with a lower shutter than 1/focal length. Beyond that, add the guides below.
That means if you are shooting with a 200mm lens, never go slower than 1/200.
The good news is that a lot of cameras now understand this rule as it’s programmed into their software, so if you are shooting in auto modes, they generally don’t exceed this rule unless they have no other choice.
Aside from the minimum rule, here are some guides to help you along (remember that these are guides, not hard and fast rules):
- Sports – 1/1000 and upwards depending on the speed of the sports.
- Children – similar to sports but less predictable – 1/320 minimum indoors, 1/500 or higher, if they are outdoors, playing.
- Panning – 1/40.
- People (portraits) – 1/125 – 1/250. It’s possible to go lower if you know you can get them to stand still.
- Landscapes – if you have a tripod, you can go as slow as your camera allows but most people shoot at 15-30 seconds if they have filters and the light allows for it. Note, that’s not 1/30, that is 30 seconds.
How to Practice
There are ways of practicing with shutter speed and understanding the impact. I generally find the road example is a good one because it gives you a good idea on how shutter impacts your photos with a repeatable subject who isn’t going to get tired.
Set your camera to shutter priority and then sit at the edge of the road taking photos at various shutter speeds examining the outcome every time you take a photo. You very quickly learn what works and what doesn’t.
When you are finished, try moving the camera with the cars (panning) and see how that impacts the photos and the backgrounds at slow shutter speeds. Experimentation is the key.
A lot of your knowledge of shutter speed will come down to your individual experiences, the subjects you are photographing and how you want to apply your artistic creativity to the photo.
Setting your camera to shutter priority will allow you to control the shutter and see what happens when you change it in the field.
Photography is about getting experience; the more experience you get, the better you become at understanding how to apply the knowledge you have learnt.
It will seem to take forever initially, but at some point, you’ll look back at your photos from a year ago and realise how far you have come.
Disclaimer: All recommendations are impartial and based on user experience, with no bias to the products or the brand. The products in this post may contain affiliate links.