The Canon EOS Digital Rebel XSi/450D Companion

CHAPTER 7

A WORD ABOUT DYNAMIC RANGE

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In fact, fill flash would have been a fine alternative to the bright window scene

that we struggled with earlier. To shoot with fill flash in Program mode, simply

press the flash button to pop up the flash, and shoot as normal.

A Word About Dynamic Range

ere is a range from very dark to very bright wherein your eyes can see detail.

Below this range, things are too dark, and above this range, things are painfully

bright. is is called dynamic range, and in humans, it’s about 18 stops wide. at

is, there are about 18 doublings of light from darkest to lightest.

Unfortunately, like all cameras, the Rebel XSi has a much smaller dynamic range

than what the human eye can perceive. About half the range, actually. is means

that, with a single shot, you cannot capture some scenes in the way your eye sees

them. For example:

e image on the right has such a huge dynamic range that it couldn’t be captured

in one shot. Instead, I had to shoot an image exposed for the shadows and one

exposed for the highlights and then combine them in an image editor.

is image has a very large dynamic range. ere are details in the shadows and

details in the highlights. It was not actually possible to capture this in one shot.

Instead, I had to take two shots, one exposed for shadows and the other exposed

for highlights, and then combine them in an image editor. Unfortunat ...