User`s manual

AW00098504000 Image Acquisition Control
Basler ace Camera Link 97
Determining whether your camera is operating with overlapped or non-overlapped exposure and
readout is not a matter of issuing a command or switching a setting on or off. Rather the way that
you operate the camera will determine whether the exposures and readouts are overlapped or not.
If we define the “frame period” as the time from the start of exposure for one frame acquisition to
the start of exposure for the next frame acquisition, then:
 Exposure will not overlap when: Frame Period > Exposure Time + Readout Time
 Exposure will overlap when: Frame Period  Exposure Time + Readout Time
For more information about determining the frame readout time, see Section 7.7 on page 115.
Guideline for Overlapped Operation with Trigger Width Exposure
If the camera is set for the trigger width exposure mode and you are operating the camera in a way
that readout and exposure will be overlapped, there is an important guideline you must keep in
mind:
 You must not end the exposure time of the current frame acquisition until readout of the
previously acquired frame is complete.
If this guideline is violated, the camera will drop the frame for which the exposure was just ended
and will declare an over trigger error. This situation is illustrated in Figure 27 with the camera set for
the trigger width exposure mode with rising edge triggering.
Frame Acquisition N
Exposure Readout
Frame Acquisition N+1
Exposure Readout
Exp
This exposure was ended too
early. The
frame will be dropped
and an over trigger error declared.
Time
Frame Acquisition N+3
Exposure Readout
ExFSTrig
Signal
Fig. 27: Overtriggering Caused by an Early End of Exposure