11
6.3.2 Trigger Mode
After a specified external event (trigger) has occurred, image acquisition is started. De
-
pending on the interval of triggers used, the camera may operate non-overlapped or over
-
lapped in this mode, when overlapped mode is enabled.
With regard to timings in the trigger mode, the following basic formulas need to be taken
into consideration:
Case
Formula
t
exposure
< t
readout
(1)
t
earliestpossibletrigger(n+1)
= t
readout(n)
- t
exposure(n+1)
(2)
t
notready(n+1)
= t
exposure(n)
+ t
readout(n)
- t
exposure(n+1)
t
exposure
> t
readout
(3)
t
earliestpossibletrigger(n+1)
= t
exposure(n)
(4)
t
notready(n+1)
= t
exposure(n)
6.3.2.1 Overlapped Operation: t
exposure(n+2)
= t
exposure(n+1)
In overlapped operation attention should be paid to the time interval where the camera is
unable to process occuring trigger signals (t
notready
). This interval is situated between two
exposures. When this process time t
notready
has elapsed, the camera is able to react to
external events again.
After t
notready
has elapsed, the timing of (E) depends on the readout time of the current im
-
age (t
readout(n)
) and exposure time of the next image (t
exposure(n+1)
). It can be determined by the
formulas mentioned above (no. 1 or 3, as is the case).
In case of identical exposure times, t
notready
remains the same from acquisition to acquisi
-
tion.
Exposure
Readout
t
exposure(n)
t
readout(n+1)
t
readout(n)
t
exposure(n+1)
t
triggerdelay
t
min
Trigger
Flash
t
flash(n)
t
flashdelay
t
flash(n+1)
TriggerReady
t
notready
Image parameters:
Offset
Gain
Mode
Partial Scan
Timings:
A - exposure time
frame (n) effective
B - image parameters
frame (n) effective
C - exposure time
frame (n+1) effective
D - image parameters
frame (n+1) effective
E - earliest possible trigger
