Canon PowerShot A100, Руководство по обслуживанию

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1-12
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Noise reduction feature for high S/N
Generally, longer exposure times generate more noise in the CCD, which can be readily visible. To reduce such
noise, the PowerShot A200/A100 incorporates automatic internal noise reduction processing.
The specific process is as follows: after exposure when the iris is closed, image capture is repeated for the same
shutter period as just used. This allows only noise to be captured as data, and this data can then be subtracted
from the image just obtained, resulting in noise reduction in the image.
However, this process applies only for shutter speeds between 1/8 and 1 second.
z SuperFine mode image quality comparable to that of RAW mode
Although the PowerShot A200/A100 is a low-priced model, it includes a “Super Fine” mode that uses a lower
compression ratio than the Fine mode. The Super Fine mode produces an image quality equivalent to
uncompressed TIFF file format, but the image storage capacity is much less than that of the JPEG baseline
recording format.
The Super Fine mode compression is not lossless, so the original data cannot be completely restored, but be-
cause the compression ratio is extremely low, the block distortion peculiar to JPEG is practically eliminated.
Also, this mode is good for general use because of the short processing time and ability to be played back even
without the TWAIN driver, because of the ordinal JPEG baseline format.
2-3 High Grade Design
z 2 : 1 Sideways Layout
As a “New Generation Camera”, the PowerShot A200/A100 has the 2:1 aspect ratio “wide & low” proportions
like the PowerShot S40/S30. This design is easy to slip into a pocket or bag, and easy to carry.
z Graphical symbols on the top of the camera show main functions at a glance
Graphical symbols representing the basic camera functions are printed on the top of the screen of the PowerShot
A200/A100 cameras. The basic functions are this easy to see at a glance on the store shelf, and serve to accent
the design.
Photo 2-5 PowerShot A100
Fig. 2-9 Graphical symbols at the top