Your camera has many automatic modes to make your life as a photographer a little easier. Each of these automatic modes was designed to isolate one or two of the many variables and settings you’ll encounter while taking pictures.
Shutter Priority Mode is an automatic mode that isolates the shutter speed setting. You can use this mode to take anything from sports action to images of flowing waterfalls.
You can get to shutter priority mode by twisting your camera’s top dial to the “S” or “Tv” setting. A few camera models might have it hidden away in the menu or it may be called something else so check your manual.
Just like the aperture priority mode allows you change the aperture settings, shutter priority mode allows you to change the shutter speed.
What is the shutter, and what is shutter speed?
Every camera works by temporarily exposing a light-sensitive surface to light from the outside world. The shutter determines the length of time the image sensor receives its light by opening and closing. Whether it’s a very tiny fraction of a second (1/500s), or it’s a much longer period of time (3 seconds), your shutter opens and closes every time you take a picture with your camera.
By changing your camera’s shutter speed, you’re either increasing or decreasing the length of time the image sensor is exposed to light. If the sensor is exposed to light for longer, the resulting image will be brighter. If it is exposed to light for less time, the resulting image will be darker. That is the first thing you will notice once you start taking images using shutter priority mode.
Freezing The Action
But there is another factor at work with shutter speeds. A shorter shutter speed can freeze action that would otherwise appear blurred if you were to use a longer shutter speed. That’s why shutter priority mode can come in handy when you’re shooting sports and or fast action photography. Just dial the shutter speed up to 1/500s, and the camera does the rest of the work. You get a nice freeze frame in the heat of the moment.
A longer shutter speed will allow you to add a motion blur to your images. The most popular use of this effect can be seen in images of flowing water like the one to the right. Because your camera’s shutter is open for longer, the water has a chance to move a little bit while the image sensor is being exposed to the light. Use a tripod to keep absolutely still and the rest of the image will stay still while the water appears somewhat blurred. The longer you leave your shutter open, the more blurred the water becomes.
How does shutter priority mode work?
Shutter priority mode is a semi-automatic mode, meaning it works by using your camera’s internal light meter, analysis the scene in front of you, and attempts to come up with an even and balanced exposure using the shutter speed you give it. Shutter priority mode attempts to make an image that isn’t too bright or too dark.
So, you choose the shutter speed, and the camera chooses everything else. One of the settings chosen by the camera is the aperture size. The aperture is the hole that light travels through to get to the image sensor. When it’s wide open, the image formed is much brighter. When it’s closed, the resulting image is darker.
When you shoot in shutter priority mode, the camera adjusts the aperture to give a balanced exposure. If the shutter speed is really fast, the camera picks a more wide open aperture to compensate for the lower amount of light hitting the sensor. If you have a really slow shutter speed, the camera picks a more closed aperture to effectively lower the amount of light coming through. Either way, it’s “trying” to get an image that is neither too bright nor too dark.