Shutter speed refers to exposure time, meaning how long the shutter stays open. It's measured in fractions of a second. A borderline shutter speed for a still image is 1/30, as that's about as long as you can hold a camera steady without external assistance.
The f/stop (also known as aperture) refers to the size of the opening in the lens that allows light through when taking photos. Aperture readings go from widest (f/smaller number) to narrowest (f/larger number). Think in terms of fractions. An f/4 aperture is wider than f/16. With control over the amount of light in an exposure, the f/stop helps determine how sharp different things in the photo appear, especially when it comes to distance.
An ISO setting measures the light sensitivity of film or a digital sensor. It is measured in numbers, such as 100, 200, 300, etc. Lower ISOs are less sensitive to light, while higher ISOs are more sensitive. Higher ISOs are referred to as "fast," as they allow you to use faster shutter speeds and narrower f/stops to still get enough light. The reverse is true for slower ISOs.
Taking Action Photos
Taking action photos begins with knowing your camera's mechanics. Action photography requires you to be quick. Therefore, you likely can't compose your shot as usual, but that doesn't mean you can't do some preplanning. For example:
- Check out your location and set up in a safe, action-packed area.
- Check your background and lighting.
- If you're photographing a sport, learn about its objectives and rules. This will help you anticipate the action and position yourself appropriately.
- If possible, talk to your subjects to see if they'll pre-plan some shots. Don't be shy when it comes to strangers. For example, for a digital file or print, an amateur athlete may be more than willing to help.
After doing your homework, there are great ways to capture the action. It all comes down to your personal preference and what type of adventure photography story you're aiming to tell. Below, you'll find three photography tips for taking action photos. If needed, refer to the sidebar on this page for helpful definitions.
- Freezing action -- If you want to freeze action in time without blurring your image, you need a fast shutter speed, such as 1/1000 (or a sports or active mode on a point-and-shoot). Depending on the lighting in your photo environment, you may need to adjust your f/stop to a wider setting because you'll be cutting down on the light let in through your shutter. Experiment to see which combinations work.
- Blurring action -- Use slower shutter speeds (or the landscape setting on a point-and-shoot) to blur your photo and illustrate speed. To keep your subject sharp while blurring everything around it, pan with a slow shutter speed. To pan, move the camera with the subject. First, start tracking your subject. Press the shutter button halfway down to start the autofocus. Then, keep moving with your subject and push the button all the way down when you want to take the photo. Track through the photo to ensure you don't stop before the exposure is complete.
- Catching action at its peak -- In some action sequences, such as when a basketball player goes up for a slam dunk, there's a moment of peak action when everything seems to momentarily freeze. If you shoot at the peak of action, it's possible to catch that stopped motion.
Ready to try these techniques? Why not get bundled up and head out for some photos in the snow? Snowshoe to the next section to learn more.