Knowing what shutter speed does is vital for controlling your images. That’s not just how it affects exposure, but changing the shutter speed has a knock-on effect that can dramatically alter the look of a photo. Here’s an explanation and some exercises for you to try.
The big temptation for photographers is to go from one extreme to another. A fast shutter can stop movement, show movement, or even blur it so much that it makes a moving subject disappear. However, many don’t realize the subtle nuances that can be achieved by changing the time the shutter is open by just one or two stops.
However, the speed you choose is dictated by factors other than just exposure.
The Effect of Proximity
Firstly, there is the moving subject’s proximity to the camera. Imagine you are sitting in a car and looking through the side window. The road near you rushes by so quickly that it is blurred. Consequently, you cannot identify any features on the road surface. Meanwhile, the distant landscape seems to pass at a more leisurely pace. So, to stop the motion of a close object, you will need a faster shutter speed.
Exercise 1
Set your lens to its widest angle and the camera’s shutter speed to 1/60 second. This speed approximates the perception of the human eye. Get a friend or family member to stand about 20 yards away and wave at you. Take a photo.
Now ask them to halve the distance and, without changing any camera settings, take another shot. Then, halve the distance again, and repeat until they are a couple of yards away. Observe what happens to the blurriness of their hand as they get closer to you.
The Effect of Focal Length
The same applies to using wide angle or telephoto lenses. A moving subject that passes slowly across the frame with a 12mm lens will be gone in a blink with a longer lens, so a faster shutter is required. Likewise, that long lens will exaggerate any camera movement. Therefore, you will require a fast shutter if you do not want to show that movement.
Exercise 2
Repeat the above exercise, but now get your friend to stand still about five yards away. Instead of them moving, zoom in on their hand as they wave.
Stopping or Showing Movement Blur
Of course, the subject’s speed will also dictate how fast a shutter you will need to stop the action. A fast-moving bird will require a faster shutter speed to stop its movement than a tortoise will.
Exercise 3
Set the camera to 1/60 second and take shots while your friend waves slowly. Ask them to speed up gradually and take more photos. You will see the hand becoming increasingly blurred with each photograph.
Your Camera Makes a Difference
The crop factor of your camera will also affect the amount of blur in a shot. A slower shutter speed on a 35mm sensor camera is needed to achieve the same amount of motion blur as you would with a Micro Four Thirds (MFT) camera, assuming the same focal length and subject distance. Similarly, an MFT camera would need a faster shutter speed to stop movement.
Don’t Copy His Settings, They May Be Wrong
No universal rules exist for stopping or blurring action with a camera. Although they can be a good guide, it’s pointless to copy others’ settings. Only experience will help you learn what settings you need for any situation.
The Same Photo at Different Shutter Speeds
Here is an example of the same photo shot at different shutter speeds. I shot these photos for this article on the West Coast of Scotland. There, the weather changes every few minutes. Therefore, the aperture and ISO settings to achieve the required shutter speed varied a bit between the shots. Furthermore, to reach some of the fastest shutter speeds, I opened the aperture to f/2.8. As a consequence, the depth of field varied too.
Let’s start with this version. It is a 75-second exposure shot at f/5.6, ISO 200, using a combination of an Urth Plus+ ND1000 filter and the camera’s built-in OM-1 Mark II Live ND feature, the inbuilt ND filter. The water is completely blurred.
Next, I removed the ND1000 filter and used just the Live ND. Here’s a 5-second version of the same shot. There’s very little difference between this and the previous version because the fast-moving water travels a long way across the frame, but close inspection shows some definition of water droplets.
At 3.2 seconds, there is a tiny amount of extra definition in the water, but it’s barely noticeable.
The following was shot at two seconds. Again, there was not much change.
The next shot was a one-second exposure. Again, the difference is minuscule.
From now on, we will start to see a bit more difference in the water between each increase in shutter speed. Here’s half a second.
Then at 1/8th of a second. There is even more detail in the water.
This is 1/15th of a second.
At 1/60th second, there is even more definition.
There comes a point when the shutter speed stops the action, and any further increase makes very little difference to the photo. In the following comparison, the photograph on the left was shot at 1/1,000 second and on the right, 1/3,200 second. They look very similar.
A Note About the Term Shutter Speed
Your camera’s mechanical shutter is made from two curtains; after one opens, the other closes. They move at the same speed, but the time gap between them changes. I guess this is why Canon cameras rejected the otherwise universal “S” on the mode dial for Shutter Priority and used “Tv” for Time Value instead. Nevertheless, most of the photography world uses “shutter speed.” A good mechanical shutter will give you speeds of 1/8,000 second or more.
With electronic or silent shutters, the curtains remain open, and the sensor is scanned electronically. Electronic shutters typically achieve much faster shutter speeds.
There are advantages and disadvantages to both, but those are for another article.
Do You Like Long Exposures?
Like with any approach in photography, there is subjectivity when it comes to long exposures. The ease with which shutters reach extremely high speeds—1/32,000 second on my camera—and extremely long exposures like the 7.6-minute shot above make such photography easier now than ever before.
Moreover, just because you can doesn’t mean you should. I could have chosen a long exposure for the next photo; I do like the effect of long exposures on water because it minimizes the scene. But in this case, I preferred to see the movement of the water.
Long Exposures Are Not Just for Landscapes
Choosing different shutter speeds isn’t limited to landscape photography. As much as I revel in stopping the movement of birds in flight, setting the shutter speed to something much slower can bring interesting results.
A Quick Word About the Other Exposure Variables
Three other factors dictate your shutter speed: the aperture, the ISO setting, and the amount of light entering the camera from the lens.
To some extent, the availability of fast and long shutter speeds is dictated by the equipment’s capabilities. The aperture is fixed between two parameters, and usually, the higher the quality of the lens, the broader the range of apertures available, especially with additional wider settings. The wider the available aperture, the faster shutter speed you can achieve.
Meanwhile, the ISO set on the camera also dictates the dynamic range and the likelihood of digital noise being introduced to the image. Some cameras can work at higher ISOs than others.
Finally, we have little control over the quantity of natural light other than reducing it by adding an ND filter. While I was shooting the demonstration pictures of the stream for this article, the light was constantly changing.
In Conclusion
Only experience will teach you what settings you need for your camera to achieve the results you want. Understanding exposure and how movements are shown or hidden by your shutter will help you achieve the results you want.
