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The hardware signal for the time t
global
is available on connector #4
(Global out see 6.3.9).
Obviously, if during exposure and readout, parts of the viewed image
are moving horizontally, this would result in image distortion. This is
why the global shutter mode may be a prerequisite for some
applications.
However, most dynamic events can be captured in 1 ms, which is a
common integration time with SLR cameras set at 1/1000 exposure.
The time shift from one row to another is only about 10 µs (fast scan).
The resulting maximum readout time of 10 ms (at full resolution)
seems to be sufficient for a broad spectrum of dynamic events.
The 10 ms is also faster than the image shift process of most frame
transfer emCCD image sensors previously used for low light
applications. If this does not influence the image recording and
processing, then rolling shutter mode will not affect it either.
Exposure time < Sensor frame readout time (Auto Sequence)
In case the required exposure time is shorter than the frame readout
time, the image is composed of two exposure bands moving from the
outside to the center of the sensor.
For example the shortest exposure time in Rolling Shutter is 100 µs
for the pco.edge 4.2.
The band of simultaneous exposure is in this case (smallest
possible height) at full resolution:
e.g. pco.edge 4.2: 100 µs / 24.93 µs (line time (see 1.2)) = 4 →
number of simultaneous rows = 8
Previous comments on image distortion (also known as Rolling
Shutter Effect) apply here as well.
band of simultaneous exposures
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