Allied Vision Alvium 1800 Series - Trigger features and UserSetDefault; Triggering with rolling shutter cameras

208Alvium USB Cameras User Guide V3.6.4
Triggering
Trigger features and UserSetDefault
See Trigger features and UserSetDefault on page 167.
Trigger delay with 1800 U-120 cameras
If sensor related parameters are changed directly before sending an external
trigger, the trigger delay can be increased. This relates to Frame rate jitter on page
215.
Triggering with rolling shutter cameras
This section describes triggering behavior for 1800 U-500m/c, U-501m NIR,
U-1240m/c, and U-2050m/c. Figure 86 shows how an external signal triggers
exposure and readout for cameras with rolling shutter (RS) sensors. Like for global
shutter (GS) sensors, readout has a constant duration, acquisition must be active
to enable exposure, the end of exposure starts readout.
Rolling shutter (RS) sensors run in cycles where readout area equals exposure area.
Overlapping triggering is not supported. If exposure time is shorter than readout
time, exposure starts with a delay:
Exposure start delay = exposure area – exposure time.
Figure 86: Triggering rolling shutter (RS) cameras
External signal
Sensor cycle state
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