First Light C-RED 3 - Triggered Acquisition and Latency

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Latency
Camera latency is the delay between the rising edge of FPS_Tint_in signal and the first valid data on
camera link. This delay depends on the tlsydel parameter value.
The table below contains typical measured camera latency in normal (CDS) readout mode full frame.
Latency for tlsydel = 324 (default)
22.2 µs
Latency for tlsydel = 54 (min)
7.4 µs
The theorical formula to get the latency is:
Latency =Tlsydel + (image width / 16) + 18) * 1/18214000
Tlsydel default value is 324, the minimum value is 54. The default value avoids seeing a disturbance
on the image in any cases. However, depending on the cropping used, the value can be decreased to
maximize the framerate.
Below some theorical latencies for several geometries:
Image width
Tlsydel
600 fps option
640
324
21,0 µs
640
54
6,1 µs
64
324
19,0 µs
64
54
4,2 µs
96
324
19,1 µs
96
54
4,3 µs
128
324
19,2 µs
128
54
4,4 µs
Triggered acquisition
This feature allows the camera to be configured to grab a specified number of frames at a specified
framerate / exposure duration.
This mode is similar to internal synchronization since framerate and integration times are controlled
through software, but the acquisition will start only after the reception of an acquisition trigger and will
automatically stop after the acquisition of a preconfigured number of images.
If a new acquisition trigger is received whereas the previous acquisition has not been completed, the
current acquisition sequence will be aborted, and a new acquisition sequence will take place.
The triggered acquisition mode is enabled using the command “set swsynchro on” and is disabled
using the “set swsynchro off” command using the CLI interpreter.
You can check if the triggered acquisition mode is on or off using the “swsynchro” command.