Understanding Exposure

For some of you, this chapter contains concepts you are familiar with. However, for others of you, dSLRs or photography in general might be new territory. And even if you're an advanced user, you may benefit from the information on evaluating your exposure using histograms and adjusting your exposure using the Nikon D7000's exposure compensation and bracketing features. This chapter covers exposure, how aperture affects depth of field, how the shutter speed is used to create different effects, and how ISO can affect both your aperture and shutter speed settings.


Understanding exposure is essential to controlling the outcome of your images. Exposure: ISO 100, f/10, 1/60 second using a Nikon 70-200mm f/2.8 VR lens at 155mm.

Exposure Overview

Exposure is the most important aspect of photography. If you don't understand how exposure is calculated, you'll have difficulty understanding how your camera chooses the settings for semiautomatic modes such as Shutter Priority or Aperture Priority. This can hinder your ability to achieve a specific effect in your image.

By definition, exposure as it relates to digital photography is the total amount of light collected by the camera's sensor during a single shutter cycle. A shutter cycle occurs when the Shutter Release button is pressed, the shutter opens, closes, and resets. One shutter cycle occurs for each ...

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