KID’S PHOTOGRAPHY BASICS: UNDERSTANDING ISO

Of all the concepts you come across in photography, ISO seems to be the one that introduces the most confusion to new and even experienced photographers, while simultaneously being almost overlooked as a key part of photography. If you are able to get a handle on when to increase or decrease your ISO when it comes to kid’s photography, you’ll have a powerful tool to give you more flexibility with your exposures, particularly in low-light situations or when you need a faster shutter speed to capture action.

For an introduction to ISO and how it works, see Part I and Part II of the Exposure Triangle series.

Review of ISO

In a nutshell, ISO represents the sensitivity of your camera’s sensor, and it can be increased or decreased. Some camera’s will do this automatically based on the settings you are using (automatic versus manual, for instance). You can also manually set the ISO when it is necessary.

Imagine you are building a house with 100 construction workers, who say it will take 10 months to build. Now, if you had 200 construction workers, it would take half as long. ISO is similar, when you double it you double the amount of light your camera can capture.

Why Increase ISO?

Every time you increase ISO, you also increase your camera’s ability to capture an exposure. For example, if you had an exposure of 1/250s f/16 at 100 ISO, by doubling the ISO you could increase the shutter speed to 1/500s or set the aperture smaller to f/32. You see, if you double your ISO you can half the other settings.

This comes in handy when you need more light, or a faster shutter speed to get the correct exposure. You’ll notice it most indoors when the light is low, as using a higher ISO setting will allow you to use a faster shutter speed so you don’t end up with blurry images.

Downside of High ISO

Like every setting, there’s a downside to using too much of it. Higher ISO levels can introduce “noise” or a grainy appearance to images – obviously not desirable. However, if you have a choice between getting a good image (correct exposure) with noise or not, then you know what to do.

Learn to Use ISO to Take Great Kid’s Photos

Figure out how to use ISO; on automatic or manual camera settings. Then next time you are stuck with getting the right exposure for your kids photos, try increasing the ISO to give you more flexibility with the other settings. Spend some time learning which situations are best for a higher ISO setting – low light is one, but also situations where you need a really fast shutter speed can benefit from boosting the ISO sensitivity.