- May 11, 2021
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A common goal of photographers far and wide is to take clear photos. Of course, there are occasions when someone might want to introduce blur into a picture, but for the most part, when an object is focused on, the primary objective is to return a photo with suitable clarity. Many times though, situations arise where photos don't have their sought after quality. The first place any experienced photographer turns to is shutter speed.
In this post, I'm going to discuss how shutter speed works on DSLR cameras and how to best achieve the results you want when you're indoors or in the field shooting photos. It's not a difficult concept to grasp, but there are fundamentals that must be understood.
Camera Shake Vs. Slow Shutter Speed Vs. Lack of FocusBefore we begin, I think it would be prudent to define the difference between a few types of blur. In general, there are three types of blurry photographs. They are lack of focus, camera shake and motion blur.
Lack of Focus: If you take a picture and what you intend to focus on is blurry, but the rest of the photo is clear, you are most likely suffering from a focus error, or lack of focus. You can pinpoint this error by looking around the photo that was taken. If the background, for instance, is clear, with no motion blur at all, but the foreground has a soft, uniform blur to it, lack of focus is what you've got. To remedy this, you'll need to look into either your camera's auto-focus or your manual focus methodology. The key to diagnosing this type of photograph is to look at the type of blur. Like I mentioned above, if it's uniform and soft, with no start or end point, it's most likely lack of focus.
Camera Shake: While looking at a photo, if you notice that all items in it exhibit a sort of movement blur, you are most likely suffering from camera shake. Camera shake is oftentimes attributed to a slower than optimal shutter speed and an unsteady hand. If a shutter speed is slow and either you or the camera is moving, the result will be an all around blurry photo that looks like it's been shaken. To remedy this, you'll need to increase the camera's shutter speed or steady the camera or both.
Motion Blur: If you take a picture and notice that a moving object in it has a motion blur, while all other objects in it are clear, you are most likely suffering from a slow shutter speed. Conversely, if you've taken a picture of a moving object and it's clear, while everything else has a motion blur, you've taken the photograph correctly. The second scenario is called proper panning and will be discussed in another post. For now, what you need to understand is to take pictures of moving objects, you either need to increase the camera's shutter speed to such a degree that everything in the photo is clear or to pan the camera as to remain focused on the moving object.
Is Your Shutter Speed Too Slow?One of the most overlooked settings on any DSLR today is shutter speed. Many amateur photographers prefer to let their cameras do the work by overusing the "P" (program) mode or one of the other automatic settings. This can lead to trouble because cameras don't always know the photographer's intent. I'll give you can example.
Oftentimes, I like to head outside during early spring to take photos of freshly budding flowers. Since spring is the only time of year the flowers I like to shoot are in this state, my time is very limited. If the sun is shining or if it's not raining, I have to get out there, even if it's windy. And trust me, much of the time it's windy.
Problems arise when I try to take pictures of flowers that are swaying back and forth because of the wind. If I choose to use program mode on my camera, the camera is taking notice of the light that's available - and that's it - and programming what it thinks the settings should be. It has no idea that my subject is moving. If it's cloudy or dark outside, for one reason or another, I'm essentially trying to take an action shot. The camera will automatically set the shutter speed to a relatively slow one because of the lack of light. If you've ever tried to capture a moving object with a slow shutter speed, you know that the resulting photo will be blurry. That's why there is a very important rule in photography:
Always take note of your shutter speed. For every single shot.
Now, you may be asking, what should my shutter speed look like to handle various conditions? Luckily, I wrote a post, earlier, that covers what various shutter speeds should be set to, based on what you're attempting to capture. I'll give you a general tip to follow here though. If you're hand holding your camera and using a shutter speed that's slower than 1/60 of a second, your resulting photographs may be blurry. Of course, there's more that goes into this, but you can safely use this speed as a guide. It's better to keep an eye on and adjust the shutter speed than to take blurry photos caused by camera shake.
By this point, you may have another question. How do we reduce camera shake? Again, I wrote posts on how to properly hold a camera and how to stabilize a camera as to reduce blur. If you don't have time to read those other posts right now, I'll give you a few options here.
1. Don't take the photo.
2. Stabilize your hand held camera by holding it properly and tight to your body.
3. Stabilize your camera by leaning it against a stable object.
4. Stabilize your camera by using a tripod.
The primary take away for this section is that you begin to focus on shutter speed and consider it one of the most important settings on your camera.
What is a Stop?A stop, in the most basic sense, can be defined as the opening that lets light through your camera lens. I talked about this in a previous post, where I discussed aperture. The aperture, in a lens, is a set of metal fins that slide along each other to increase or decrease the size of the opening in a lens that allows light in. It's much like the iris in a human eye. The larger the hole, the more light passes through. The smaller the hole, the less light.
To many photographers though, a "stop" is merely a measure of light. It needn't be related to only aperture. A stop can be measured by any source of light that's available for a scene.
For instance, let's say that you've got a setting where there's one source of light. If you double the amount of light available from what you initially had, you'd be increasing it by "one stop." The same is true if you cut your light source in half. If you did this, you'd be decreasing your light source by one stop.
If you discuss stops as related to the amount of light that's allowed to pass through your camera's lens, you'd be referring to the size of your lens's aperture and your camera's shutter speed. For example, if you set your camera's shutter speed to 1 second and then halved it to 1/2 second, you'd be reducing the sensor's availability to light by one stop. Similarly, if you increase or decrease your aperture size by double or half, you'd be increasing it or decreasing it by one stop.
Let's go through a real world example for a moment. Let's say you have four equal light sources for an indoor shoot. When you focus your camera on your subject and meter it, the camera tells you the shutter speed is set to 1/500 of a second (fast). If you turn off two of your sources of light and then meter your camera again, it should tell you that the shutter speed is set to 1/250 of a second (slower). The reason the shutter speed decreased by half is because your light source was reduced by half. In photographer speak, your light source was reduced by one stop (less light), so your shutter speed was increased by one stop (light passes through longer).
So to review, a "stop" is a relative measure of light. To increase lighting by one stop, you double your light source or slow your shutter speed by half. To decrease lighting by one stop, you half your light source or double your shutter speed.
Working With Shutter PriorityWhen you set your camera to shutter priority, you are most likely after one of two things. You either want to take an action photo that's ultra still and clear or you want to take an action photo that's got some blur to it. Shutter priority is great at handling both of these types of photos, but in order to take advantage of this setting, you'll need to know what's happening inside your camera and lens when you are using it.
Most DSLR cameras have a dial at the top of it with some letters marked all around it. To turn on shutter priority, turn the dial until the "S" (Nikon and Sony) or "Tv" (Canon) is lined up with the small tick mark. Once you do this, you'll be in shutter priority and will be able to adjust the shutter speed at will. For assistance with this while using your specific camera, please refer to your manual.
If you're new to cameras or are studying further into the hobby or profession, you've probably heard folks telling you to get away from automatic mode. The reason they tell you this is because when you're in one of the auto modes, all your camera is doing is attempting to meter based on the available light around you. It doesn't know what your intentions are as far as adding or eliminating blur from your photos. I've dealt with this on many occasions while taking my spring time flower photos. For the types of pictures I was referring to in one of the previous sections in this post, shutter priority is a perfect solution.
The great thing about taking advantage of shutter priority mode is that when used, your camera is still in a sort of an auto mode. The only area you're taking control of is how fast the shutter curtain slides across the camera's sensor. When you choose a shutter speed, your camera will decide on an appropriate aperture value as well as an ISO value based on the available light in your setting. With this in mind, you'll have the freedom to make time stand still, add movement to your photos or pan to your heart's content.
I have a word of warning, though, when using shutter priority. If you decide to use a very slow or a very fast shutter speed, your lens may not have a compatible aperture setting to allow or restrict the light making it through to the camera's sensor. For instance, if you want to really crank up your shutter speed and set it to 1/4000 of a second for the most clear and still of shots, your camera lens's aperture might not open large enough to let the light your camera's sensor needs in. And if you continue to take the photo, there's a good chance it will turn out underexposed. The same is true for the opposite. If you slow down your shutter speed to such a degree, your aperture might not close far enough to block the light in your setting, which may result in an overexposed photo.
Reciprocity Between Shutter Speed & ApertureThe relationship between shutter speed and aperture is fairly simple to comprehend. It's sort of like algebra - when something happens to one side, the opposite must happen to the other side. In photography, while in shutter priority mode, if you set your shutter speed to 1/250 of a second, your camera may set the lens aperture to f/8, based on how much light is available. If you then slow your shutter speed by half (one stop), your camera will most likely shrink the lens aperture by one stop, or to f/11. Basically, when you're shooting in shutter priority mode, your camera will always try to balance out the light that hits the sensor by appropriately adjusting the size of the aperture. This is called, "reciprocity."
Reciprocity is the law of the relationship between shutter speed and aperture size. The law tells us that a halving or doubling in shutter speed is equivalent to a one stop change in aperture. Each change either increases or decreases light by one comparable stop.
How To Control Motion With Camera Shutter SpeedWhen considering shutter speed, it's helpful to think about your camera freezing a specific duration of time. If your shutter speed is very fast, the duration of time you capture will be very "tight" or small. In general, the time you capture with a shutter speed above 1/250 of a second will be clear, with very little blur. Conversely, if you set your camera to use a slower shutter speed, it'll be capturing a longer duration of time. If you're shooting action or movement, chances are, your photograph will exhibit blur.
Have you ever wondered how photographers take those pictures of, let's say, waterfalls, where the water is either frozen very clearly in time or moving as smooth as silk? To take both of those types of photos, they manipulate shutter speed.
Here's a real world example. Let's say someone wants to go out and visit their favorite waterfall on a sunny day. They can get fairly close to the falling water, so if they wanted to (which they do), they could take a photo of each and every water droplet so they display clearly and very still in their photograph. How would they do this?
Well, on a sunny day, the camera's shutter speed will do a fairly good job of capturing the falling water at 1/250 of a second in shutter priority. There will be very little blur or movement. If the photographer bumps the shutter speed up to 1/1000 of a second, the falling water will be that much more clear. It will look as though it's frozen in time with virtually no movement at all. Just a reminder - as I mentioned above, when dealing with an extremely fast shutter speed, be sure your lens's aperture can handle it. Either that, or use your exposure compensation or ISO to deal with the relatively little light allowed to touch your camera's sensor.
If that someone wasn't interested at capturing still water and was more interested in taking one of those really cool moving, flowing, silky waterfall shots, they would have to set their shutter to a much slower speed. Even if they set the shutter to 1/30 of a second, that most likely wouldn't capture the effect they're looking for. Remember, the goal is flowing movement of the water in a stationary environment. And for this type of photography, a tripod is definitely necessary.
If the photographer adjusts the shutter speed to something slower, such as 1/20 or 1/15 of a second, the water will flow much more in the photo.
List of Shutter Speed IncrementsIf you recall, I talked about shutter speed increments in one of my previous posts. In that post, I told you, in a general sense, what a particular range of shutter speed might be useful for. In the final section of this post, I'm going to discuss shutter speed increments one more time, but from a different angle.
I'm going to list the common shutter speed increments found on mostly all DSLR cameras. They are:
Do you notice anything interesting about the above speeds? Well, if you're good at math, you can most likely tell that each shutter speed (except for one) is a doubling or halving of the one before or after. Pulling from a previous section of this post, each of these increments would be considered a "stop (or step)."
Now, if you're scratching your head because your digital camera has many more available shutter speeds than what I've listed above, you're not going crazy. The additional shutter speeds are considered 1/3 or 1/2 stops. And by having these available stops, your creative control increases.
If you'd like to discuss what I've covered above, please leave a comment below. Also, if you're interested in learning more about photography, please be sure to click the photography forum link above.