Camera Operation
Falcon 4 Camera User's Manual
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Gain and Black Level Control Details
Gain and black level adjustments are available in the Falcon4 series of cameras. Depending on the
model of camera, adjustments are available at the sensor as an analog variable and / or in the
digital domain. The gain and black level controls can make small compensations to the acquisition
in situations where lighting varies and the lens iris cannot be easily adjusted. Optimal gain and
black level adjustments maximizes the Falcon4 dynamic range for individual imaging situations.
The user can evaluate Gain and Black Level by CamExpert.
Features and limitations are described below.
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Analog Black Level offset is expressed as a digital number providing a ± offset from the
factory setting. The factory setting optimized the black level offset for maximum dynamic
range under controlled ideal dark conditions.
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Analog Gain is represented by two numbers for each tap. The AnalogAllRaw1 is the
maximum value of the ADC counter and is common for all taps. The AnalogTapX are the
minimum values for the specified ADC counter. To increase the gain, the user must
decrease the difference between these two numbers. In the future the analog gain will be
expressed as a multiplication factor. It is applied at the sensor level, before any FFC. The
increased gain increases the sensor’s dynamic range but with a non-proportional increase in
noise.
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[Digital Before FFC]Global FPN provides a constant component to the FPN Coefficients.
This value is calibrated in the factory but it can be adjusted relative to the factory setting (
factory setting). See the BlackLevel register’s DigitalAll1[Digital Before FFC] option. The
value is expressed as a floating point to allow for increased accuracy when processing a
frame sum of more than 1 frame.
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[Digital After FFC] Background Subtract is a digital number that is used to reduce the
baseline pixel value. When combined with the system gain, this value is used to increase
contrast in the final output. See the BlackLevel register’s DigitalAll2[Digital After FFC]
option. The value is expressed as a floating point to allow for increased accuracy when
processing a frame sum of more than 1 frame.
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System (Digital) Gain is expressed as a multiplication factor applied after the Analog Gain
and any FFC stages. When combined with the background subtract, this value is used to
increase contrast in the final output.
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Background Add is a number added to the image data before it is clipped at zero. This
value can be used to prevent the image clipping to zero.
Preliminary