Welcome back for photo tip Tuesday! The main answer to last week’s question “What are you interested in learning about photography”?” seemed to be “Um, everything!” That’s kind of a lot of ground to cover, so we’re going to take this slowly with time for you to practice along the way.

This week, I’m starting a three part series on getting the correct exposure in your images. If you set your camera to Auto, this is exactly what it is trying to do—read the scene you point it at and get the correct exposure. Indoors, this often happens by firing the on-board flash, which typically leads to less than stellar results. Rather than simply telling you to turn your flash off, I want to explain the three on-camera variables that go into producing the correct exposure and how you can manipulate them to get the results you want.

One little caveat at the outset—you’ll probably want to keep your camera’s owner’s manual handy if you’re truly serious about learning photography. I am not an expert in every camera body out there, so I can’t tell you how to physically make the changes to your settings like I’ll suggest. Your owner’s manual will tell you exactly how to do that.

Let’s start by defining the three things that go into getting a correct exposure: shutter speed, aperture setting, and ISO. This week I want to focus on shutter speed and what it does to your images.

The shutter speed is the setting that decides how quickly your lens opens and closes to allow light to reach the sensor. Shutter speed is measured and shown on your camera in increments of seconds or fractions of a second. A larger number (1, 1/50) leaves the shutter open for longer and allows more light to enter your camera than a smaller number (1/200, 1/500). A large number can also add blur to your image, either of your subject’s movement if you’re shooting a non-stationary object or from blur if you’re holding your camera with too slow of a shutter speed. The opposite is also true—a faster shutter speed will freeze motion, whether it be a fast-moving child or droplets of water falling through the air.

Let’s break this down a little more.

Fast shutter speed: 1/400 or faster means action frozen in time. Depending on how fast things are actually moving in your image, you may be able to freeze motion at a lower shutter speed, but this is a good rule of thumb for sports photography or moving water. (For all my photography posts, each image will have a caption that shows the shutter speed (ss), aperture (ap), and ISO for your reference. The shutter speed is in bold.)

ss 1/3200, ap 2.8, ISO 100

ss 1/500, ap 2.5, ISO 100

ss 1/500, ap 2.2, ISO 100

ss 1/1600, ap 2.8, ISO 100

Slow shutter speed: Anywhere from 1/125-1/400 can freeze slow or non-moving things fairly well, but subjects that are quickly moving may be blurred. A shutter speed of 1/100 or slower means more likelihood of generally blurred images.

ss 1/320, ap 2.8, ISO 400

This image is very similar in subject matter to the black and white above. But the shower shutter speed (1/320 in the color image and 1/1600 in the black and white) blurs the rain drops in the one and freezes the spinkler’s water droplets in the other. You can still tell that both are water drops, but they are much more clearly defined with a faster shutter speed.

A few more examples:

ss 1/200, ap 2.5, ISO 3200

ss 1/200, ap 2.2, ISO 100

ss 1/125, ap 2.2, ISO 3200

See the blurred frog and ribbon in this image? And the less-than-crisp legs and feet? Slow shutter speed.

A good rule of thumb when hand-holding a camera (not using a tripod) is to not let your shutter speed number (the 100 in 1/100) fall below double the focal length of your lens.

If reading that last sentence just made you go “HUH?”, here’s what I mean. If you’re using an SLR, you have a lens on your camera that has numbers on it. For my favorite lens, here’s a shot of what those numbers are and where they’re located.

“Canon Lens EF 85mm 1:1.8”

The “85mm” part is the focal length. It tells you not only the length of the lens, but also the amount of zoom that your lens provides. For larger numbers, there is more zoom, or less of the scene in front of you included in your shot. For smaller numbers, there is less zoom, or more of a scene included in a shot. If you’re photographing your child on a soccer field from far away, you’ll want a bigger number to get zoomed in close. For photographing a room interior, on the other hand, you’ll want smaller numbers, or a wide-angle lens, to get the whole room in the picture.

So once you know the focal length of your lens, keep your shutter speed at least double that number (so for my 85mm lens, that would be a minimum shutter speed of 1/170) to avoid adding blur from my own movements.

Now, the easiest way to get a photography concept down is to take about 1000 pictures and practice. I don’t recommend jumping into Manual mode just yet if you’ve never tried it and don’t know how to read your in-camera meter (that’s a future post!). Try putting your camera on shutter priority mode—this is the setting that allows you to change the shutter speed and you camera will select the aperture and ISO for you. On Canon cameras, this is the Tv setting, on Nikons it’s S mode. Then you can wander around your house and try different shutter speeds in different settings. Your flash will not fire in a shutter priority mode, so be aware of where the light is coming from—practice near a window with indirect light if you can. Chasing your kids around a park is another good way to practice making adjustments. They won’t stop moving and wait until you get your settings just right, but you can play and practice at the same time.

I’ll be back next week with aperture and reading your in-camera meter! If you practice with different shutter settings this week, I’d love to see your results. Link up in the comments or drop me an email at jan [at] janiphotography [dot] com. I can’t wait to see your images!