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19 Use cases 139
19 Use cases
19.1 Introducing acquisition / recording possibilities
There are several use cases concerning the acquisition / recording possibilities of the camera:
19.1.1 Generating very long exposure times
Since
mvIMPACT Acquire 1.10.65
Very long exposure times are possible with mvBlueFOX. For this purpose a special trigger/IO mode is used.
You can do this as follows (pseudo code):
TriggerMode = OnHighExpose
TriggerSource = DigOUT0 - DigOUT3
Attention
In the standard mvBlueFOX DigOUT2 and DigOUT3 are internal signals, however, they can be used for this
intention.
Note
Make sure that you adjust the
ImageRequestTimeout_ms
either to 0 (infinite) or to a reasonable value
that is larger than the actual exposure time in order not to end up with timeouts resulting from the buffer timeout
being smaller than the actual time needed for exposing, transferring and capturing the image:
ImageRequestTimeout_ms = 0 # or reasonable value
Now request a single image:
imageRequestSingle
Then the digital output is set and reset. Between these two instructions you can include source code to get the
desired exposure time.
# The DigOUT which was chosen in TriggerSource
DigitalOutput* pOut = getOutput(digital output)
pOut->set();
# Wait as long as the exposure should continue.
pOut->reset();
Afterwards you will get the image.
If you change the state of corresponding output twice this will also work with
wxPropView
(p. 77).
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