The shutter speed is probably the factor which has the greatest impact on an image. By adjusting the exposure time by only a few stops, you’re able to completely change the appearance of an image. But what exposure time is best for landscape photography? Should you use a long exposure or should you work with shorter ones? When will adjusting the shutter speed have the greatest impact?
In this article, I’ll share three case studies where I compare how adjusting the shutter speed has impacted the final images. I don’t believe that either is better than the other (in each case) but it’s important that you’re aware of the differences so it becomes easier to convey the story or emotions you desire.
What is a Long Exposure?
I’ve had many discussions with fellow photographers regarding the exact definition of Long Exposure. At first thought, most consider a long exposure to be an image where the clouds are dragged across the sky or moving water looks like silk or ice. However, this is judging solely based on the visual aspect of the image. Is it not still considered a long exposure if you don’t see its effect? Wouldn’t a 20-second exposure be 20 seconds no matter what?
The definition most of my photography friends have agreed upon is that a long exposure begins when you can’t take a sharp image handheld. Normally, this is at about 1/50th of a second with a wide angle lens.
Case Study #1 – Waterfalls
Waterfalls are often ideal to start experimenting with long exposures. Since the water is moving quickly, you don’t need an extremely long exposure just to capture some motion. In fact, you’ll need a very quick shutter speed to avoid capturing any motion at all.
The choice of shutter speed has an extremely high impact on the image. You might not even need a filter to begin capturing the motion of water in your shots. However, I find waterfalls to be tricky to photograph at times because of this. The different shutter speeds have such a big impact that the entire mood (and story you tell) of your image quickly changes. So, consider what you wish to convey.
If it’s a huge waterfall with a lot of power you might want to use a quick shutter speed to capture its raw power and beauty. While a smaller waterfall might be more appealing when you use a slow shutter speed (long exposure). Experimentation is always the key when working with shutter speeds.
For the image above, I chose to use a shutter speed slow enough to require the use of a tripod but not so long that the water would become completely blurred. The textures in the water help build the overall atmosphere of the image and it compliments the rawness. By keeping some texture in the water, I’ve also strengthened the composition. When a longer shutter speed was used (see below), many of the lines in the foreground were lost and the flow wasn’t as natural anymore.
When lengthening the exposure time to 20-seconds, the image lost a lot of its raw and natural feel, which was what I wanted to convey. Now, the image has an unnatural appearance and even though it’s still visually pleasing, it’s not as interesting anymore.
A long shutter speed wasn’t ideal since the river was flowing so quickly. Had the water been slower, a 20-second exposure might have done a better job. So, when photographing a waterfall make sure that you keep in mind how quickly the water is flowing, as this will have a great impact on your choice of shutter speed.
Had I used a faster shutter speed than on the first image (for example 1/500th) the image would have a different impact yet again. Such a quick shutter speed would freeze most of the water and remove the sense of motion shown in the first image. Instead, there would have been a lot of texture in the water but no movement to compliment it. That would have resulted in a messy and, again, less appealing image.
Case Study #2 – Seascapes
When working with images that have more than one moving element (for example the sky and the water), you’ve got multiple factors to consider when choosing a shutter speed. Not only will the choice of shutter speed determine how the sky appears but it’s also crucial for the appearance of the water. In fact, since the water is what’s moving the quickest, that is where you’ll see the biggest difference (just as with the waterfalls).
For the image above, I used a shutter speed of 0.6 seconds. In the grand picture of long exposures this is still a relatively short shutter speed, and for some, it doesn’t even qualify as a long exposure. However, despite the shutter speed being only 0.6 seconds, there’s quite a lot of motion in the image. Since the waves were coming in fast the camera was able to register a significant amount of motion within that short time.
Personally, I’m a big fan of exposures between 0.5 seconds to 1.5 seconds when photographing seascapes (especially when using a low perspective like this). The shutter speed is long enough to capture the motion but it’s also fast enough that there’s still a lot of texture in the water. The lines that come as a result of the slow shutter speed do a significant job in improving the composition.
In the second image, I increased the exposure time to 30 seconds, allowing the camera to register motion for a longer period of time. As you can see, the texture that was the previous image is lost and the water has completely changed its appearance. Now it looks more like ice, or some sort of solid state.
However, the clouds are also considerably different than in the first seascape. By using a 30-second exposure the camera has also registered motion in the clouds, resulting in a more dynamic sky. When the clouds are dragged across the sky, such as above, you’ve got an extra factor to consider for your composition. In this scenario, the clouds are moving towards the horizon, creating a series of extra lines that help lead your eye through the image. Often this can be a great advantage.
I don’t believe that one is necessarily better than the other but, again, it’s important to understand how the choice of shutter speed (exposure time) will impact the image. When working with a slow shutter speed you’re introduced to several new factors (such as the helpful leading lines in the sky) and being aware of them will make the process of learning long exposure photography easier.
Case Study #3 – Generic Landscape
Once you remove the second element of motion, the choice of shutter speed becomes somewhat less crucial. Still, there will be a big difference between a 30-second exposure and a 1-second exposure if you’ve got some movement in the clouds. But the difference between a 0.5 second and 5-second exposure is less significant for a generic landscape and a seascape or waterfall photo.
It’s not uncommon for me to see someone using an ND Filter when photographing a mountain on a cloudless day. This is very common when first using filters, as you want to use them all the time. However, a 2-minute exposure won’t look any different than a 1/100th of a second exposure when there aren’t any moving elements in the image. After all, an ND filter doesn’t create motion, it registers it.
The image above is a typical example of when a long exposure wouldn’t make a big difference. I used a 1/5th second exposure time for this particular image but had I used a 30-second exposure with filters instead, it still would have looked more or less the same. Simply put, it wouldn’t have been beneficial to use a long exposure on this scene.
It isn’t until you’ve got at least one moving element that the true power of a long exposure photography appears (remember, this can be something as simple as grass moving in the wind). In the image below, you see the same scene but this time with clouds in the sky. The shutter speed I used for this image was 1/15th of a second, which means that I wasn’t able to capture any motion – yet.
Once clouds had appeared and there was one element of movement in the frame, a long exposure would have an impact on the image. Since the clouds were moving I was able to capture the motion and, again, create a more dynamic image.
For the image above I increased the exposure time to 30-seconds. By increasing it that much you can clearly see how the sky has changed and how the overall mood of the image has changed along with it. Unfortunately, the clouds were moving sideways. Had the clouds moved towards or away from me, the image would have greatly benefited from a long exposure and taken advantage of the leading lines that would have helped to lead the eyes towards the structure. Since the clouds were moving sideways, the extra leading lines in the image aren’t as helpful, even though they look nice.
Summary and Conclusion
After reading this article I hope you have a better understanding of how the shutter speed will affect an image and when increasing or decreasing it will be beneficial. There’s no “correct” way of doing it, and in the end, which image you prefer depends on what you’re looking for in your image. However, as I’ve mentioned multiple times, it’s extremely important that you understand how a longer or shorter shutter speed will impact the image. By understanding this, you’ll be able to save a lot of time in the field and ultimately create better images.
Remember, a slower shutter speed can affect the appearance of an image when there’s more than one moving element within the frame. A slow shutter speed is not going to make a difference when there are no moving elements.