Exposure can be confusing – even to us photographers that have been around for a while. If you are trusting your camera in automatic modes while taking kid’s photos, you are letting it set the combination of elements (aperture, shutter speed, and ISO) to create what it thinks is the “correct” exposure, but does that mean that it’s right for your image? Not always…
The problem here is that your camera’s “brain” looks at the amount of light and dark in a scene and chooses settings to try to get a balance so your image is neither too light nor too dark, for the most part it doesn’t know what exactly you need to have correctly exposed (i.e. your child/subject). The problem here is that it can be wrong, so at the very least it can help to learn how to override your exposure setting to get the image to appear the way you want it to.
Here’s an example:
Shooting “into the sun” tends to make your background really bright, while your subject is shadowed. Your camera tries to find balance by going for the middle, so your subject may be underexposed while your background is still fairly bright. By adjusting the exposure higher you can ensure that your subject is correctly exposed.
These types of situations can occur any time you have a contrast of light/dark, or even just a lot of light, such as with sunsets, photos with bright skies, snow scenes, etc. Your camera may tend to underexpose and you’ll have to correct it to get the right balance of light and dark.
First, you have to get out of automatic modes, as your camera gives you little to no control over exposure in these modes. Start with P (Program mode) if you are just getting off automatic, later you can move to modes that offer more control. Next, identify your exposure button; typically it’s marked Av+/- (check your owner’s manual to make sure). By holding down this button and moving your wheel to adjust the exposure up or down – your camera will respond by changing the appropriate settings to comply.
If you are finding that your camera regularly under or overexposes your shots then you may want to learn more about the different ways your camera can measure exposure (more on this later). Alternatively, you can learn to read your histogram to identify when there are parts of your image that are too light or dark. The key lesson here is that your camera is not smarter than you are; if you want really great images then you need to be in control.