Allied Vision Alvium G1 - Triggering with Rolling Shutter Cameras

Triggering and timings
209Alvium G1 User Guide V1.7.0
Triggering with rolling shutter cameras
This section describes triggering behavior for Alvium G1-500m/c and G1-2050m/c
cameras with rolling shutter sensor. Figure 78 shows how an external signal
triggers exposure and readout for cameras with rolling shutter sensors. Like for
global shutter sensors, readout has a constant duration, acquisition must be active
to enable exposure, the end of exposure starts readout.
ERS 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 78: Triggering rolling shutter cameras
No Conditions Results
1 Exposure time is shorter than readout time. Trigger 1 starts exposure 1 with a delay
2 Exposure time is shorter than readout time, but
longer than for exposure 1.
Trigger 2 starts exposure 2 with a delay shorter
than for exposure 1.
3 Exposure time is longer than readout time Trigger 3 starts exposure time without a delay.
Because the exposure area is longer, also the
readout area is longer than for triggers 1 and 2
4 Exposure area is ongoing. Trigger 4 is ignored.
5 Readout area is ongoing Trigger 5 is ignored.
6 Readout area is finished. Exposure time is
longer than readout time.
Trigger 6 starts exposure 6 without a delay
Table 112: Triggering results versus conditions
TriggerSelector values for rolling shutter cameras
Cameras with rolling shutter can be triggered using AcquistionStart,
AcquisitionEnd, or FrameStart for
TriggerSelector.
Cameras with rolling shutter cannot be triggered using ExposureStart or
ExposureEnd for
TriggerSelector.
External signal
Sensor state
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Readout areaExposure area
DelayП
DelayП
Idle Readout areaExposure area Readout areaExposure area
ПExposure start delay