The Canon EOS Digital Rebel XSi/450D Companion

PROGRAM MODE

GETTING CREATIVE WITH PROGRAM SHIFT

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Getting Creative with Program Shift

In the previous chapter, you learned about the effects that different shutter speed

and aperture choices have on your final image. You saw that by controlling shut-

ter speed, you can choose how much you want to freeze or blur motion, and

that by controlling aperture, you can choose how much you want to blur out the

background. You also learned that these parameters have a reciprocal relation-

ship. If you change one, you can change the other to compensate.

e Rebel XSi has a lot of different ways to change shutter speed and aperture,

allowing you to take complete creative control of motion stopping and depth of

field.

If you’ve taken some shots already in Program mode, then you’ve seen that it

works just like Full Auto mode. When you half-press the shutter, the camera au-

tofocuses and meters. Once it has determined a shutter speed and aperture that’s

appropriate for the scene, it displays those values on the status display inside the

viewfinder and on the back of the camera.

As I mentioned in the previous chapter, the camera’s built-in meter aims for a

shutter speed that is appropriate for handheld shooting and an aperture that’s not

too extreme. But as you’ve learned, many different combinations of shutter speed

and aperture yield the same exposure. Some of these combinations will have a

faster or ...