In a modern SLR, for instance, microprocessor-controlled sensors
determine the exact amount of light needed to expose a picture at the moment you press the
shutter release. The lens automatically adjusts the size of its opening to admit the correct
amount of light, and the mirror mechanism that usually lets you look through the viewfinder
flips up and out of the way, allowing light to reach the film. Finally, the aperture opens,
and the shutter slides open for the programmed amount of time. Point-and-shoot cameras,
in contrast, don??™t use mirror mechanisms to let you see through the lens before the shot, so
there are fewer moving parts at the moment of exposure??”but the trade-off is that you don??™t
see the picture you??™re about to take as accurately with a point-and-shoot.
42 How to Do Everything: Digital Camera
Go to the corner photo store, and you??™ll find two kinds of film: negative film and slide
film. They work a little differently, but the end result is similar. When you use color negative
film, also referred to as reversal film, the film itself becomes a negative image of the scene you
photographed. After processing, which includes letting the film sit in a chemical bath that coaxes
the grains of silver to visually materialize on the film, the negative is used to create positive
prints of the scene.
Pages:
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93