To get the perfect exposure, the perfect amount of light has to hit your sensor. If you let in too little light, your photographs will be dark and generally gray-looking. If you let in too much light, your photos will be very bright and generally washed-out in color.
We use the in-camera light meter to help us get the perfect exposure. Your light meter looks something like the photo above. It will tell you if your aperture, shutter speed, or ISO are out of balance.
A Good Exposure
The goal is to get your light meter balanced in the center. If the light meter is moving toward the plus sign, your photo will be overexposed. To move it back towards the middle, you need to decrease the amount of light coming in the camera by closing down the aperture, increasing the shutter speed, or lowering the ISO. You can choose any of those methods to let in less light depending on the vision you have for your photo.
If the light meter is moving toward the minus sign, your photo will be underexposed. To move it back towards the middle, you need to increase the amount of light coming in the camera by opening up the aperture, decreasing the shutter speed, or increasing the ISO. Any of these will work. You need to choose the one that will work best for your photo.
Let’s say that I am outside taking photos of my kids. I want the background blurry (shallow depth of field), so I open my aperture to f/3.5. The last time I was taking pictures I had my shutter speed set to 1/60th of a second. As I look at the light meter in the viewfinder there are several lines moving toward the plus sign. That tells me that I have too much light coming into the camera. to keep this in balance, I need to decrease the amount of time my shutter stays open. I turn increase the shutter speed until the light meter comes more into balance. My new shutter speed is 1/500th of a second.
I could also have taken this photo at f/10 and 1/60 since it would have been an equivalent exposure. I would have had the same nicely exposed photo. However, the photo I ended up with would have been much different--namely, the background wouldn’t have been as blurry as I wanted.
Tips to Remember:
- Your light meter isn’t perfect. The great thing about digital is that you can see what your photo looks like immediately. As you are learning, use that feedback to make adjustments.
- You may notice that your digital SLR consistently underexposes slightly. You can make adjustments by just always knowing that your camera is in balance when the light meter in your camera shows 1 or 2 lines toward the +. Get to know your camera and how it exposes.
Don't Miss the Next Posts in This Series!
I hope this series has helped you Master Shooting in Manual Mode. If you’ve missed any of the posts in the series, you can go back and read/review them at any time by following these links!