NAC Image Technology ST-839, User Manual

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External input/output signal circuit
9-52
(00400)
Simple Synchronized Recording
Synchronized recording can be easily performed because the multiple HX/GX series cameras or the fx series
cameras with the exposure start signal (EST) input function use exposure pulse output (EPO).
Additionally, synchronized recording is also possible with other cameras that have equivalent functions.
Since there is a possibility that the time precision cannot be guaranteed due to signal delays or time
changes, the limitation is that all of the cameras must have the same frame rate.
For simple synchronized recording, the system is comprised of cameras that are deemed master or slave.
One of the cameras in use can be the master camera, and the others are all slave cameras. If a HX
・ GX
series camera is the master camera, the exposure pulse output (EPO) signals for this camera are connected
to the exposure start signals (EST) input for all of the other cameras.
If combining both the HX
・ GX series and the fx series, the fx series EST input has the specification of
starting exposure only at Ｈ→Ｌ edge signals, while with HX ・ GX series master camera, the output polarity
is set to reverse and the L level is output during exposure. Also, the EST input setting for the slave HX ・ GX
series cameras are Ｈ→Ｌ edge signals.
If combining with other cameras, refer to the manuals to match the signal polarity.

Since the exposure pulse output (EPO) signals are equivalent to the exposure time (shutter
time), if set to a short exposure time, the pulse width will also shorten. Be sure to take
adequate caution of conversion to a suitable interface and cable properties for signal
transmission. With an inappropriate method of use, error pulses may be detected or pulses may
be lost, preventing transmission.