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CM-080GE/CM-080GE-RA / CB-080GE/CB-080GE-RA
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Exposure Time Abs (GenICam Standard)
This is a function specified in the GenICam standard.
The shutter speed can be entered as an absolute exposure time in microseconds (μs) in
register address 0xA018. The entered absolute time (Time Abs) is then converted to
programmable exposure (PE) value inside the camera.
The below calculating formula shows the relationship between the PE value used by the
camera for the different readout modes and the value entered in register 0xA018. As the
calculation is based on rounding down to the closest integer, precise values may not always
occur.
The relation between PE value and Time Abs:
Normal readout PE= 2 + INT (Exposure time -85) µs / (1420/33750000)
V Binning readout PE= 2 + INT (Exposure time -103) µs / (1730/33750000)
INT means integer (rounded down).
The following table shows minimum value and maximum value for each readout mode.
Minimum value
Maximum Value
Normal Scan
85µs
33,238 μs
2/3 Partial Scan
85µs
24,951 μs
1/2 Partial Scan
85µs
20,912 μs
1/4 Partial Scan
85µs
14,685 μs
1/8 Partial Scan
85µs
11,656 μs
V-Binning Scan
103 µs
20,351 μs
GPIO in combination with Pulse Width Trigger
More precise exposure time can be obtained by using GPIO in combination with Pulse Width
Trigger mode. The clock generator and counter can be programmed in very fine increments.
As for the setting example, refer to chapter 6.5.1.
9.3. Auto-detect LVAL-sync / a-sync. accumulation
This function replaces the manual setting found in older JAI cameras. Whether accumulation
is synchronous or a-synchronous in relationship to LVAL depends on the timing of the trigger
input.
When trigger is received while FVAL is high (during readout), the camera works in LVAL-
synchronous mode, preventing reset feed trough in the video signal. There is a maximum
jitter of one LVAL period from issuing a trigger and accumulation start.
If trigger is received when FVAL is low, the cameras works in LVAL-asynchronous mode (no
delay) mode. This applies to both pre-select (PS) trigger mode and pulse width control trigger
(PW) mode.