SVS-Vistek ECO Series, Manual

Page: 22 / 104

SVS-VISTEK
Feature description 22
Rolling Shutter Limitations
Due to the principles of rolling shutter, some standard features of SVS-
Vistek cameras are not applicable. This relates to following
Ex p os u r e C on tr ol wi th Rol l i ng Shu t te r
In the graphics above, it is easy to see that external exposure control does
not make sense with rolling shutter. Exposure delay and Overlapping
Exposure as well is impossible with rolling shutter.
RO I wi th Rol l i ng s hu t te r
With Rolling shutter the whole sensor has to be read out – always. That
means applying ROI will reduce the amount of final data being
transmitted out of the camera (and the framerate might rise, due to the
limited bandwidth of the interface). Nonetheless, the maximum achievable
framerate with applied ROI will be the maximum framerate of the sensor
reading the full sensor area (internal full sensor speed), please refer to the
relating sensor specs.
6.1.3 Exposure speed
Frames per second, or frame rate describes the number of frames output
per second (1/ frame time). Especially GigE and USB cameras cannot
guarantee maximum predictable framerates with heavy interface bus
load.
Maximum frame rate might depend on
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Pixel clock
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Image size
>
Tap structure
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Data transport limitation
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Processing time
6.1.4 Acquisition and Processing Time
The camera has to read the sensor, process the data to a valid image
and transfer this to the host computer. Some of these tasks might are
done in parallel. This implies the data transfer does not end immediately
after end of exposure.