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Controlling image capture
MARLIN Technical Manual V2.4.0
127
CCD For the CCDs the uncertainty time delay before the start of exposure depends
on the state of the sensor. A distinction is made as follows:
FVal is active the sensor is reading out, the camera is busy
In this case the camera must not change horizontal timing so that the trigger
event is synchronized with the current horizontal clock. This introduces a
max. uncertainty which is equivalent to the line time. The line time depends
on the sensor used and therefore can vary from model to model.
FVal is inactive the sensor is ready, the camera is idle
In this case the camera can resynchronize the horizontal clock to the new
trigger event, leaving only a very short uncertainty time of the master clock
period.
Model Camera idle Camera busy
Marlin F-033 33.33 ns 27.03 µs
Marlin F-046 33.33 ns 32.17 µs
Marlin F-080 50 ns 63.50 µs
Marlin F-131 25 ns Not applicable
Marlin F-145 50 ns 92.25 µs
Marlin F-146 30 ns 54.78 µs
Marlin F-201 30 ns 64.5 µs
Table 48: Jitter at exposure start (no binning, no sub-sampling)
Note
L
• Jitter at the beginning of an exposure has no effect on
the length of exposure, i.e. it is always constant.
• By default, the Marlin F-131, the CMOS sensor uses glo-
bal shutter, so it cannot be re-triggered until the previ-
ous image has been read out.