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• Europe 50 cycles (100 fluctuations/s) whereas in
• USA, Japan and other countries it is 60 Hz.
This means the camera must strictly be coupled to this frequency. In conjunction with auto exposure this can only
be maintained by using a timer based generation of external trigger pulses. This is a behavior of both sensor types:
CCD and CMOS.
Note
It is not enough to use "Setting -> Base -> Camera -> GenICam -> Acquisition Control -> Acquisition
Frame Rate" for this, as there are small fluctuations in this frame rate if the exposure time changes.
These fluctuations lead to oscillations (see settings marked with red boxes in Figure 1). The "Acquisition
Frame Rate" will only provide the exact frame rate if auto exposure is turned off.
As shown in Figure 1, it is possible to set ("mv Exposure Auto Mode") which part of the camera handles the auto
expose (device or the sensor itself; pink boxes). Using "mvSensor" as "mv Exposure Auto Mode", it is possible
to avoid oscillations in some cases. The reason for this behavior is that you can set more parameters like "mv
Exposure Auto Delay Images" in contrast to "mvDevice". However, as mentioned above it is recommended to use a
timer based trigger when using auto expose together with continuous acquisition.
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