Exposure can be a tough concept for some beginning photographers to grasp. In fact, given today’s advanced camera technology and the ability of most cameras to capture images that are correctly exposed on their own, even some people who have been shooting for awhile still don’t have a good understanding of exposure.
So I know what some of you might be thinking. The camera does it for me. My camera can figure out correct exposure. In fact, it does a pretty good job most of the time. So why should I bother to learn about exposure?
Here’s why. Because the “correct” exposure isn’t necessarily the right exposure.
Let me explain.
Exposure is the amount of light reaching your camera’s image sensor when you snap a photo. When we talk about “correct” exposure, we are talking about balancing the effects of three factors:
- The aperture size, or the size of the lens opening.
- The shutter speed, or the amount of time light from the lens is allowed to enter the camera.
- The ISO, or the light sensitivity of the camera’s image sensor.
The Exposure Triangle is a graphical description of this relationship.
The thing to keep in mind when considering this relationship is that there is more than one combination of aperture, shutter speed and ISO that will correctly expose any photo. And each of these combinations will produce a “correctly” exposed photo, but each will also produce a different looking photo.
So, when if comes to correct exposure, you have some choices. And each of them will have real consequences on the look of the image that you create.
For example, the two images below are properly exposed. But they look very different.
So if you want to get better as a photographer, it’s important to understand exposure and to get involved in the process.
If you’re having a hard time understanding exposure concepts, I think the two videos below will help.
The second video, from Tony Northrup, expands on this by showing exposure concepts in action.