Genie Nano-CL C2450, Руководство пользователя

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Genie Nano-CL Series™ Operational Reference
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Offset/Gain Control Details (On-Semi Python sensors)
The Gain and Black level functions are applied at the sensor and/or on the digital image values
output by the sensor, as described below.
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Gain Selector = Sensor Analog: The gain function is a linear multiplier control in 0.01 steps
within the sensor hardware.
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Gain Selector = Sensor Digital: The gain function is a linear multiplier control in 0.1 steps
within the sensor hardware.
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Important: Digital noise increases linearly and quickly with higher gain values. Users should
evaluate image quality with added gain.
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Gain (Raw): Shows the raw sensor control for each gain stage or an alternative method to
control sensor gain.
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Black Level: This offset variable exists within the sensor. The On-Semi sensors allow an offset
range between 0 and 255 DN. The factory settings default value for each sensor used by
various Nano models, is recommended as per the sensor manufacturer design specifications.
Note: With the factory default offset, testing a camera’s black output in 8-bit mode may show
a 2 DN value difference across the image. Changing the Black Level value up or down will push
sensor noise (present at the sensors native bits per pixel) to fall within one 8-bit value, thus the
noise becomes hidden.
On-Semi Python Sensors Gain Stage Diagram
Analog Gain Control
Post Digital Gain Control
On-Semi Sensor Gain Stages
Analog
Black Level
Control
Digital Digital
Digital Gain Control
OnSemi Sensor Artifacts with Fast Readout Mode
Applicable only when Flat Field Correction is purposely disabled.
When Fast Readout mode is active (cameras with OnSemi sensors), the row blanking and row
readout occurs in parallel in the sensor. This reduces the total frame readout time resulting in a
faster maximum frame rate. As a consequence of this mode there are minor column artifacts (of
very low DN), typically of no significance and irrelevant for many imaging systems. Note that these
column artifacts will become more prominent as sensor gain is increased.