SVS-Vistek SHR 10GigE, Manual

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the sensor is fully open. While being fully open this is the time where flashing
should happen. In the final scanning time, less and less pixels are sensitive to
light until the sensor light sensitivity will finish.
Rolling shutter limitations
Due to the principles of rolling shutter, some standard features of
SVS-Vistek cameras are not applicable.
l
External exposure control (expose while trigger signal active) does not make
sense with rolling shutter
l
ROI with rolling shutter: 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 read-
ing the full sensor area (internal full sensor speed), please refer to relating
sensor specs.
Calculate frame rates
According to the calculation below, the requested times for scanning through all
lines of the sensor will affect maximum frame rate calculation as well.
In this example, the camera is an exo183 with 3672 lines and 54 dummy lines.
Each line takes 22.2 ms readout time (depending on CameraLink tap con-
figuration). The camera does have about 300 µs exposure time delay at worst
case.
Frame rate calculation with exo183CCL with rolling shutter
lines 3672
dummy lines + 54
total lines 3726
readout time 1x3_1Y 22,2 µs * 3726 = 82717,2 µs
exp delay + 300 µs
frame readout time 83017,2 µs
This is minimum time for camera readout with 0s exposure time.
Exposure time has to be added:
frame readout time 83017,2 µs
exposure time 2500 µs
total frame time 85517,2 µs
maximum sensor acquisition time 1/ frame time 11,6 fps
note: readout time 1x2_1Y = 32,63 µs
5 Feature description 41