NAC Image Technology SP-642, Руководство пользователя

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(00292)H 8 - 3
8.2 External Sync Recording (EST)
When performing EST recording with GX cameras, the shutter must be set so the sensor
exposure time is shorter than the cycle (or shortest time frame) of the external sync signal.
If the following sync signal pulse is received during sensor exposure, proper recording will not
be possible.
With HX and GX-8 cameras, A-EST synchronization is possible with great precision.
With A-EST synchronization, set the exposure time to 1/2 or less the cycle of the external sync
signal.
With fx cameras, you must set the frame rate for two or more times that of the external sync
signal.
Example) If GX-1 external sync signal:2400Hz -> cycle:416.7us
If the GX-1 image size is 640x480, set the shutter (exposure time) to 413us or less.
Since the fx requires a frame rate setting of 5000pps, the exposure time is at the max of 200us.
■ Setting and Confirming the HX, GX and Q camera Shutter Values Set
With EST Signal:2400Hz, frame size:640x480
Connect the HX and GX cameras with HXLink to display the “Camera Details” dialogue.
(Select the HX or GX camera with “Detailed Settings” or from the item list and right click to
select).
Click the frame rate button on the recording parameters in the “Camera Details” dialogue to
display the “Custom Settings (Frame Rate, Frame Size)” dialogue.
Set the frame rate to 2400 (input 2400 on the keyboard) and the frame size to 640x480 and click
“OK”.
Click the shutter button on the recording parameters.
The “Custom Shutter Settings” dialogue appears, and the possible settings for the shutter range
are shown under microSEC. The maximum value noted there is the maximum value that can be
set for the shutter during 2400Hz EST recording. Set the shutter time in this dialogue and click
“OK”.
When recording with this setting and the EST signal is greater than the assumed frequency of
2400Hz, multiple EST signals show up during the frame exposure determined by the shutter
setting, and in that case, the recording stops. Recording will not function until the EST signal
frequency drops and recording can be conducted at the shutter setting.
In this case, either make sure the EST signals do not get higher than the frequency or change the
shutter settings to shorten the exposure time.
Also, if changing the shutter settings to extend the exposure time, check the shutter settings in
advance and set a low frame rate to the camera.
■ Connection for EST Recording
Input the external sync signal to the HX or GX or Q camera or GX-HUB for EST recording.
With fx cameras, input the external sync signal to the AUX connector on the rear panel. Refer to
the fx camera user's manual for details.
To input direct sync signals to GX camera, connect the J1 cable to the J1 POWER connector
and input the sync signal to the EST1 or connect the J3 cable to the J3 ETHERNET connector
and input the sync signal to the EST2.