Basler Pioneer User Manual page 131

Image Acquisition Control
starts when the ExTrig signal falls. Figure 33 illustrates timed exposure with the camera set for
rising edge triggering.
ExTrig Signal Period
ExTrig Signal
Exposure
(duration determined by the
exposure time parameter)
Fig. 33: Timed Exposure with Rising Edge Triggering
Trigger Width Exposure Mode
When trigger width exposure mode is selected, the length of the exposure will be directly controlled
by the ExTrig signal. If the camera is set for rising edge triggering, the exposure time begins when
the ExTrig signal rises and continues until the ExTrig signal falls. If the camera is set for falling edge
triggering, the exposure time begins when the ExTrig signal falls and continues until the ExTrig
signal rises. Figure 34 illustrates trigger width exposure with the camera set for rising edge
triggering.
Trigger width exposure is especially useful if you intend to vary the length of the exposure time for
each captured image.
ExTrig Signal Period
Exposure
ExTrig Signal
Fig. 34: Trigger Width Exposure with Rising Edge Triggering
When you operate the camera in trigger width exposure mode, you must use the camera's
exposure setting to set an exposure time. The exposure time setting will be used by the camera to
operate the trigger ready signal.
You should adjust the exposure setting to represent the shortest exposure time you intend to use.
For example, assume that you will be using trigger width exposure and that you intend to use the
ExTrig signal to vary the exposure time in a range from 3000 µs to 5500 µs. In this case you would
use the exposure setting to set the exposure time to 3000 µs.
If you are using the trigger width exposure mode and the camera is operating with overlapped
exposures, there is something you must keep in mind. If the action of the ExTrig signal would end
the current exposure while readout of the previously acquired image is still taking place, the camera
will automatically continue the exposure until readout of the previous image is complete. This
situation is illustrated Figure 33 for rising edge operation. On the first cycle of the ExTrig signal
shown in the figure, the signal rises and falls while readout is taking place. Normally you would
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