| Functionality |
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Functionality
Image Aqcuisition
Readout Modes
The FX cameras provide two different readout modes:
•
Sequential readout:
Frame time is the sum of exposure time and readout time. Exposure time of the next image
can only start if the readout time of the current image is finished.
•
Simultaneous readout (interleave):
The frame time is determined by the maximum of the exposure time or
of the readout time, which ever of both is the longer one. Exposure time of the next image can start during the
readout time of the current image.
The following figure illustrates the effect on the frame rate when using either the sequential readout mode or the
simultaneous readout mode (interleave exposure).
Figure 13: Frame rate in sequential readout mode and simultaneous readout mode
Sequential readout mode
For the calculation of the frame rate only a single formula applies: frames per second equal
to the inverse of the sum of exposure time and readout time.
Simultaneous readout mode (exposure time is less than readout time)
The frame rate is given by the readout time.
Frames per second equal to the inverse of the readout time.
Simultaneous readout mode (exposure time is greater than readout time)
The frame rate is given by the exposure
time. Frames per second equal to the inverse of the exposure time.
The simultaneous readout mode allows higher frame rate. However, if the exposure time greatly exceeds the readout
time, then the effect on the frame rate is neglectable.
Note:
In simultaneous readout mode image output faces minor limitations. The overall linear sensor reponse
is partially restricted in the lower grey scale region.
Note:
When changing readout mode from sequential to simultaneous readout mode or vice versa, new
settings of the BlackLevelOffset and of the image correction are required.
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