Chapter 3: Hi-Ho, Hi-Ho, Choosing an ISO

In This Chapter

arrow.png Dialing in ISOs

arrow.png Keeping a rein on ISO

arrow.png Peeking at an ISO gallery

ISO (International Standards Organization), the camera’s sensitivity to light, is one of the three ways you can control a photo’s exposure. Working together, ISO, aperture, and shutter speed let in light and react to that light.

ISO sensitivity is a subject that can get lost in the mix. Controlling your camera’s ISO speed doesn’t offer you the same creative possibilities that you get by setting the aperture. Nor does ISO play the same role as shutter speed in capturing a crisp photo. However, you’ll find that ISO is just as important.

This chapter is devoted to ISO: explaining what it is, what effect it has on exposure, and how you can manage it. You see some examples of photos with lower and higher ISOs, and I share some tips on keeping ISO speed and noise levels under control.

Turning Up the Volume on ISO

The term ISO used to mean something else, but has changed so that it now describes how sensitive the digital camera sensor is to light. ISO is sometimes called ISO sensitivity or ISO speed.

Varying ISO speed

The amazing thing about having a digital sensor ...

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