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EXPLANATION OF TERMS
AE
Auto Exposure; by using a built-in exposure meter, the camera determines the
correct exposure value, which is a combination of shutter speed and aperture value.
AE Lock
The camera will fix and memorize the exposure value with AE lock. For example, if a
photographic subject is placed in the center and exposure value of the composition
is fixed, the brightness of the background will not influence the exposure, even if the
composition changes and the subject is moved from the center of a screen. (AE lock
button must be used).
AF
Auto Focus; by using a built-in sensor, camera adjusts the focusing automatically.
AF Lock
In AF shooting mode, you can lock the focus on the main subject. For instance,
compose the desired subject in the center of the viewfinder. With the focus fixed at
the same setting, you can re-compose the picture with the subject off-center and
take pictures. (Please press the shutter button “Half-way” to use this feature with the
Sigma DP1).
Aperture
The lens opening of the iris diaphragm inside the lens. The amount of light, which
strikes the image sensor, is adjusted by the iris diaphragm. The f-number (Focal
Length/Diameter of the Aperture Opening) describes the size of this opening, the
size of the hole can be made larger or smaller. A large aperture (low f-number) gives
bright results and a small aperture (high f-number) gives darker results.
Auto Power-Off
To save battery power, the DP1 camera will automatically turn itself off if it is not
used for a period of time.
CMOS
Complementary Metal Oxide Semiconductor (CMOS) can perform signal amplication
on a per-pixel basis. Significant current flows only during the switching operation.
Therefore a CMOS image sensor can scan data rapidly, sustain high-speed
operation and consume less energy. Recent technological and production
improvements in digital imaging systems are making CMOS more and more
competitive in terms of image quality and cost.
Color Temperature
The numerical expression of the tone of the light, produced by a light source. The
standard unit for color temperature is degrees Kelvin (K). The sunny daylight used
as a standard near 5600 K. Low color temperature implies warmer more yellow/red
light while high color temperature implies a colder more blue light. The typical color
temperature of Tungsten light is 3200 K grade, a personal computer is 9300 K.
Exposure.
The amount of light reaching the image sensor’s surface. The exposure is controlled
by the combination of aperture and shutter speed.