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Alvium USB Cameras User Guide V3.3.0
Specifications
Triggering
The following table shows how the shutter mode impacts available frame rates.
Reducing the area for ROI reduces readout time. The relations in
apply
only if exposure time is shorter than readout time.
Sensor shutter types and triggering
Differences between sensors with global shutter (GS), rolling shutter (RS), and
global reset shutter (GRS) are explained in
Shutter types affecting image readout
on page 195. Triggering behavior differs between cameras with global shutter (GS)
and rolling shutter (RS). See
on page 181 for details.
Sensor type
Shutter mode
Trigger mode
Available frame rates
ROI frame rates
Global shutter (GS)
Global shutter (GS)
Freerun
Maximum values
Increased values
Global shutter (GS)
External trigger
Maximum values
Increased values
Rolling shutter (RS)
Rolling shutter (RS)
Freerun
Maximum values
Increased values
Rolling shutter (RS)
External trigger
Halved values
Increased values
Global reset shutter (GRS) Freerun
Maximum values
No increase
Global reset shutter (GRS) External trigger
Maximum values
No increase
Table 16: Frame rates depending on shutter modes and trigger modes
Achieved frame rates may not match specified values
•
Some sensors have an exposure start jitter that may reduce maximum frame
rates.
•
Your individual setup may cause delays in data transmission.
Bandwidth adjustments
Consider the bandwidth available for camera payload depends on your individual
hardware, the operating system, software and drivers, and your application. We
recommend you to adjust
DeviceLinkThroughputLimit
and
MaxTransferSize
to your requirements. See
Operating systems and bandwidth
Interdependencies between ROI and ExposureTime values
Changing parameters for ROI can affect values for
ExposureTime
, such as
minimum, maximum, and increments, but
ExposureTime
itself as well. We
recommend you to set:
•
ROI values
•
DeviceLinkThroughputLimit
before you set values for
ExposureTime
.
See
Value changes by feature interdependencies
on page 191 for details.
MaxTransferSize
can have an impact as well.