Basler A400K, Руководство пользователя

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Basic Operation and Features
Basler A400k 3-11
DRAFT
3.5 Gain and Offset
3.5.1 Gain
Gain on A400k cameras is adjustable
within a range from 0% to 100% where 0 %
correspond to the minimum gain and
100 % correspond to the maximum gain.
The minimum gain is always 0 dB. At an
offset of 0 %, the maximum gain is
approximately 13 dB. The maximum
achievable gain decreases as the offset is
increased. See Table 3-1.
The default gain is 0%.
As shown in the graphs in Figure 3-10,
increasing the gain setting increases the
slope of the camera’s response curve and
results in a higher camera output for a
given amount of light. Decreasing the gain
setting decreases the slope of the
response curve and results in a lower
camera output for a given amount of light.
Increasing gain also increases noise. The
signal to noise ratio decreases as gain is
increased.
3.5.1.1 Setting the Gain
You can set the gain by using the Camera Configuration Tool Plus (CCT+) or by using binary write
commands from within your own application to set the camera’s control and status registers
(CSRs).
With the CCT+
With the CCT+ (see Section 4.1 ), you use the Gain setting in the Gain & Offset parameter group
to set the gain.
By Setting CSRs
You can set the gain by writing a value to the Raw Gain field or to the Absolute Gain field of the
Gain CSR (see page 4-20 ).
Section 4.2.2 explains CSRs and the difference between using the “raw” field and the “absolute”
field in a CSR. Section 4.3.1 explains using read/write commands.
Offset Gain in dB @ 100% Gain
0% ~ 13 dB
100% ~ 8 dB
Table 3-1: Max. Gain
Figure 3-10: Response at Various Gain Settings