Shutter Speed and What the f means To You

I know you’ve seen it, you’ve looked at it, you’ve tried to figure it out but for the life of you, you just can’t make any sense of it. I know, I was like you. What is up with the f in photography? It’s really pretty simply once you understand the concept behind it. F stands for f-stop. It is the number that denotes the aperture setting on your camera. I talked in the last post about this. The smaller the hole, the slower the f-stop, the larger the hole the faster the f-stop. Well Shutter Speed works in conjunction with the aperture to help you take a correctly exposed photo. They work hand in hand.

Shutter speed can be confusing enough in its own right let alone trying to figure out how aperture fits in. Hopefully, I can make things a little more clear. When you are looking at your camera you are probably looking for a setting that says Shutter Speed right? Well unfortunately you aren’t going to find one. The shutter speed setting is usually displayed on your camera as the Tv number. No not television but the initials Tv. Shutter speed is a little more intuitive and you will see the setting listed something like 1/4, 1/60, 1/250, 1/8000. These numbers stand for fractions of a second that the shutter actually stays open. 1/4 is exactly that, the shutter is actually staying open for 1/4 of a second to capture the required amount of light. At the same time 1/8000 is the shutter staying open for 1 8000th of a second to capture light, that is a very, very fast speed. So you can see in the sense that unlike aperture, shutter speeds get faster the larger the number and slower with the smaller number.

A fast shutter speed of 1/500 or more will freeze most motion on the photo. Shutter speeds of 1/30 or slower enables you to shoot in low light conditions however with slower speeds comes some complications. A slower speed means that it takes longer to capture the light and thus means the camera needs to be still for longer than normal. Any camera shake while the shutter is open will cause the photo to become blurry. For very slow shutter speeds a tripod or other method of keeping the camera still is necessary.

So, how does shutter speed and the f-stop work together to make an equivalent exposure? You have to keep in mind that ISO plays a major role in these equations as well but with the following examples you should begin to get the idea. Your subject is going to depend on what settings you want to use.

Let’s assume that you are outside and see a beautiful landscape. With a landscape photo you will want most of the image to be in focus so you know that your f-stop number needs to be f 8.0 or higher.  For our example we will go with an f 8.0. The shutter speed depending on the brightness of the day will need to be around 1/250 or higher even as high as 1/2500. For our example it is a reasonably cloudy day so the shutter speed can be 1/250 and an ISO of 400. This will give you a crisp clear sharply focused image. Now at the same time if you are in the same setting but you want to take a picture of something closeup and in focus and the background more out of focus. This will require a faster f-stop, say 5.6, and a faster shutter speed. The reason for the faster shutter speed is that because you are using a faster f-stop or larger hole thus capturing more light, the shutter needs to be open for less time thus capturing a more accurately exposed image. A f-stop of f 5.6 would require a shutter speed somewhere around 1/500. Starting to make sense?

The same concept can work for an indoor shot as well. Let’s say you want to take a portrait photo of your daughter in a reasonably lit room. Now it’s not an extremely well-lit room so it is going to require a slower shutter speed. A slower shutter speed is going to require a slower aperture. An example would be that a shutter speed of 1/60 would require an f-stop of f 8 or higher. The higher number the f-stop the more crisp the image.

You can easily explore ways to play with shutter speed by choosing the Shutter Priority option on you camera. This is usually the option listed as Tv. Shutter Priority allows you to adjust the shutter speed and the camera will adjust the aperture.

Play around with the different settings and be mindful of the aperture value your camera gives for certain shutter speeds in certain light. This is an easy way to learn different settings.

Until next time, Happy Shooting!

-Robert Hillis