Sony a (alpha) DSLR-A100 Operating Instructions Manual page 45

Zone Matching
You can keep the image from becoming overexposed or underexposed when shooting a high-
keyed or low-keyed subject.
This function is also available for a RAW file.
1 Display the ISO/Zone Matching screen with the function dial and the Fn button (page 43).
2 Select [Lo80] or [Hi200] with v/V/b/B on the controller, then press the center of the controller.
• [AUTO], [100], [200], [400], [800] and [1600] options are used for ISO sensitivity (page 44).
Lo80
Hi200
• The ISO sensitivity is set to the equivalent of ISO 80 in [Lo80], and of ISO 200 in [Hi200].
• When zone matching is used, the contrast setting in the color mode is deactivated.
• Refer to the following table to determine the flash range.
Aperture
F2.8 1 – 3.8 m (39 3/8 – 149 5/8 inches)
F4.0 1 – 2.7 m (39 3/8 – 106 3/8 inches)
F5.6 1 – 1.9 m (39 3/8 – 74 7/8 inches)
This keeps the image from becoming underexposed. Use in
low-key (predominantly dark) scenes is recommended, as the
image tends to become whitish.
This keeps the image from becoming overexposed. Use in
high-key (predominantly light) scenes is recommended, as
the image tends to have heightened noise level.
Zone Matching
Lo80
1 – 4.3 m (39 3/8 – 169 3/8 inches)
Hi200
1 – 6 m (39 3/8 – 236 1/4 inches)
1 – 3 m (39 3/8 – 118 1/8 inches)
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