About 2 years ago I purchased my very first Nikon D40x DSLR camera without even knowing what a DSLR meant. Being frugal in nature, I was trying to find ways to save money on my up and coming wedding by purchasing this camera. I mistakenly believed that I could find a friend that was competent enough to help me out, but as I used the D40X myself I realized the challenge in mastering it. I never did find a friend that I entrusted enough to capture my whole wedding, but what I did gain was a new found interest in digital photography. Since than I’ve come a long way in my photography education, and it would be my honor to plant my seeds inside of you, my seeds of knowledge.

In this article I will explain 2 important camera settings that will allow you to control camera exposure, and they are called the Aperture and Shutter Speed. And for those who don’t know, under exposure is when your image is too dark, over exposure is when your image is too bright. Our goal is to get the perfect exposure, which is the middle ground of over exposure and under exposure.

Aperture

Think of aperture like the iris in your eye balls. When the surrounding light is too dark, your iris will open wide to let more light into your eye balls. As it gets brighter, your iris will become smaller to decrease the amount of light into your eye balls.  The purpose of the iris opening and closing is to have everything you see become properly exposed, which is controlled automatically by your eye balls. Now take your eye balls and look at the diagram below and you will see a donut shaped object called a “aperture”.

The aperture is represented by a number, usually preceded by an F. In many cameras the aperture ranges from F2 all the way through F16. The lower number means your aperture is open wider, letting more light in. The opposite is true for the higher number aperture, which means you will be letting in less light by making the aperture smaller.

Shutter Speed

Now the shutter speed is the second function you will need to control camera exposure. You will have to imagine that there is a small curtain inside your camera that opens and closes, just like your eye lids open and close.  And just like the aperture, the shutter speed comes in a range of numbers. But these numbers represent actual time, in seconds, from about 1/4000 of a second all the way to 1+ seconds. Most cameras would display 1/4000 of a second as being just 4000. You will usually be using shutter speeds that are less than a second in length, and only in rare occasions, would you ever need to go above a second.

To dumb it down for you, the shutter speed would basically be the amount of time it takes for your camera to blink. The faster it blinks the less light it allows, and the slower it blinks the more light it will let in. It’s really as simple as that.

The Shutter Speed has another key property which is it’s ability to control motion blur. If you want to stop the action, of let’s say of a women kicking a man in the nuts, you would need to increase your shutter speed. Slowing down your shutter speed would leave you with images that have blurred motion. It is the job of the photographer to decide what type of image would work best for the situation, and that’s where the creativity comes to play.

Equivalent Exposure

Once you finally understand the working of shutter speed and aperture, you will need to learn another tidbit of knowledge which will assist you in capturing great images with speed and precision. It’s called Equivalent Exposure, which can best be described through a diagram.

Let’s say that you have the perfect exposure for your lighting situation with your aperture at F8 and your shutter speed at 60.



But you wanted to stop the action, so you increase your shutter speed to 500. What this means is that you are letting less light into your camera. So to compensate you need to open up your aperture to F2.



Now you want to create a blurry motion shot, so we slow our shutter speed to 15 which would over expose our image now. Now to re compensate for adding more light, we need to shrink our aperture down to F16.

So all these settings I’ve displayed is equivalent, meaning F8:60 is equal to F2:500 is equal to F16:15. They all display the same amount of exposure, but the look of the image will be different. Also notice how when I subtract 3 positions less light on the shutter speed, I add 3 positions more light on the aperture and vice versa. To imagine how this works, you need to picture balancing people on a seesaw, and that’s all there is to shutter speed and aperture.

Conclusion

Controlling camera exposure by setting your aperture and shutter speed is the first lesson a beginning photographer should learn. It is actually quite confusing in practice, but as you take more and more pictures you will become faster at setting your exposure. It’s almost like playing Dance Dance Revolution for the first time, and looking foolish as you try to match the arrows with your feet. But as you become experienced, you will still look foolish, but at least now matching those arrows becomes second nature.

So anyone who owns an SLR, I have a little assignment for you. Practice with your camera by going into different lighting situations, and take one shot with motion blur and one that’s stop action. Make sure your shots are well exposed, and do this with your camera set to the manual mode. You can share some of your images with me on this website by posting a link to your image in the comments. Or you can message my by e-mail at contact@curiosity-media.com.