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Chapter 5
Image Acquisition
Determining the Scan Mode
The
maximum frame rate for selected scan mode
is determined by the partial scan mode and
binning mode. Because the amount of data read out of the sensor is less in 1/2 or 1/4 scan mode,
the readout takes less time, and you can achieve faster frame rates. The same is true of binning.
When binning is enabled, the readout takes less time, and you can achieve faster frame rates.
Refer to the
sections of Chapter 3,
, for more
information about partial scanning and binning.
Use the maximum frame rate specifications for your smart camera in your scan mode in
Appendix A,
, to determine the
maximum frame rate for selected scan mode
.
Determining the Exposure Time
The minimum frame period depends on exposure time, lighting mode, and trigger delay.
A longer exposure time results in a longer frame period, and a slower maximum frame rate.
Determining the Lighting Mode
If you are not strobing a light using the Direct Drive or the external strobe outputs of the smart
camera, the smart camera can expose one image while it is reading out the previous image,
allowing for the highest possible frame rates. Figure 5-3 illustrates this relationship. The smart
camera receives the trigger for the second image while it is still reading out the first image. The
first image readout finishes before the second image readout begins.
Figure 5-3.
Image Acquisition Without Strobing
1
Beginning of First Image Readout
2
Beginning of Second Image Exposure
3
Beginning of Second Image Readout
Trigger
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