Custom Synchronization Settings: OptiHub

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This page lists out the custom synchronization settings under the Synchronization pane when using the OptiHub.

To customize sync settings when using the OptiHub or the OptiHub 2, change the Sync Mode to Custom Synchronization. Using this mode, users can configure the master sync source of the camera system as well as the output signals from the hub for triggering other external acquisition devices.

For general instructions on customizing sync settings when integrating external devices, read External Device Sync: OptiHub guide.

  • The OptiHub 2.
  • The OptiHub 2.

    • Synchronization Control[edit]

    Sync Mode[edit]

    Determines which USB synchronization protocol is used: OptiSync or Wired Sync. Each protocol is explained below.

    Info2.png
    OptiSync
    Wired Sync

    Difference Between OptiSync and Wired Sync

    OptiSync
    • The OptiSync is a custom camera-to-camera synchronization protocol designed for Flex series cameras. The OptiSync protocol sends and receives sync signals over the USB cable, without the need for RCA sync cables. This sync method is only available when using Flex 3 or Flex 13 cameras connected to the OptiHub.


    Wired Sync
    • The Wired Sync is a camera-to-camera synchronization protocol using RCA cables in a daisy chain arrangement. With a master RCA sync cable connecting the master camera to the OptiHub, each camera in the system is connected in series via RCA sync cables and splitters. The V100:R1 (Legacy) and the Slim 3U cameras utilize Wired Sync only, and therefore any OptiTrack system containing these cameras need to be synchronized through the Wired Sync. Wired Sync is optionally available for Flex 3 cameras.

    Internal Sync Freq (Hz)[edit]

    This option is only valid if the Sync Input: Source is set to Internal Sync. Controls the frequency in Hertz (Hz) of the OptiHub's internal sync generator. Valid frequency range is 8 to 120 Hz.

    Global Sync Offset (us)[edit]

    This option is only valid if the Sync Input: Source is set to Sync In or USB Sync. Controls synchronization delay in microseconds (us) between the chosen sync source signal and when the cameras are actually told to expose. This is a global system delay that is independent of, and in addition to, an individual camera's exposure delay setting. Valid range is 0 to 65862 us, and should not exceed one frame period of the external signal.

    Sync Input[edit]

    The OptiHub custom synchronization settings with input source set to Internal/Wired.
    The OptiHub custom synchronization settings with input source set to Sync In.

    To setup the sync input signals, first define a input Source and configure desired trigger settings for the source:

    • Internal Sync sets the OptiHub as the sync source. This is the default sync configuration which uses the OptiSync protocol for synchronizing the cameras. The Master OptiHub will generate an internal sync signal which will be propagated to other (slave) OptiHub(s) via the Hub Sync Out Jack and Hub Sync In Jack, in OptiSync mode. If WiredSync is used, the internal sunc signal will still be generated but it will be routed directly to the cameras via the camera sync chain cables. The camera system will be a master in this case.
    • Sync In sets an external device as the sync source. The camera system will be a slave in this case.
    • USB Sync sets an external USB device as the sync source. This mode is for customers who use the Camera SDK development kits and would like to have their software trigger the cameras instead. Using the providede API, the OptiHub will be send the trigger signal from the PC via the OptiHib's USB uplink connection to the PC. The camera system will be a slave in this case.

    Source: Internal/Wired[edit]

    The Internal/Wired input source uses the OptiHub's internal synchronization generator as the main sync source. You can modify the synchronization frequency for both Wired and OptiSync protocol under the Synchronization Control section. When you adjust the system frame rate from this panel, the modified frame rate may not be reflected on the Devices pane. Check the streaming section of the status bar for the exact information.

    Source: Sync In[edit]

    The Sync In input source setting uses signals coming into the input ports of the OptiHub to trigger the synchronization.

    Input Trigger: Can select from Either Edge, Rising Edge, Falling Edge, Low Gated, or High Gated signal from the connected input source.

    Input Divider: Allows a triggering rate compatible with the camera frame rate to be derived from higher frequency input signals (e.g. 300Hz decimated down to 100Hz for use with a V100:R2 camera). Valid range is 1 (no decimation) to 15 (every 15th trigger signal generates a frame).

    Source: USB Sync[edit]

    (The camera system will be the slave) sets an external USB device as the sync source. This mode is for customers who use the Camera SDK development kits and would like to have their software trigger the cameras instead. Using the providede API, the OptiHub will be send the trigger signal from the PC via the OptiHib's USB uplink connection to the PC.

    Input Trigger: Determine which input trigger is used for synchronization. Either Edge, Rising Edge, Falling Edge, Low Gated, or High Gated.

    USB Sync-In Control: Only available if Source is set to USB. Allows the user to allow or block trigger events generated by the internal sync control. This option has been deprecated for use in the GUI. Valid options are: Gate-Open and Gate-Closed.

    Input Divider: Only available if Source is set to External Sync. Allows a triggering rate compatible with the camera frame rate to be derived from higher frequency input signals (e.g. 360Hz decimated down to 120Hz for use with a Flex 13 camera). Valid range is 1 (no decimation) to 15 (every 15th trigger signal generates a frame).

    Input Trigger Options
    Trigger Description
    Either Edge Uses either the rising or falling edge of the pulse signal.
    Rising Edge Uses the rising edge of the pulse signal.
    Falling Edge Uses the falling edge of the pulse signal.
    High Gated High Gated mode triggers when the input signal is at a high voltage level, but stops triggering at a low voltage level.
    Low Gated Low Gated mode triggers when the input signal is at a low voltage level, but stops triggering at a high voltage level.

    External Sync Output[edit]

    Sync signals can also be sent out through the output ports of the OptiHub to slave devices in the synchronization chain.

    Pulse Type[edit]

    Selects condition and timing for a pulse to be sent out over the External Sync Out jack. Available Types are: Exposure Time, Pass-Through, Recording Level, and Recording Pulse.
    External Sync Output Options
    Output Description
    Exposure Time Outputs a pulse signal when the cameras expose.
    Pass-Through Passes the input signal to the output.
    Recording Gate Outputs a constant high level signal while recording. Other times the signal is low. (Refered as Recording Level in older versions).
    Gated Exposure Time Outputs a pulse signal when the cameras expose during a recording only. (Refered as Recording Pulse in older versions).


    Polarity[edit]

    Selects output polarity of External Sync Out signal. Valid options are: Normal and Inverted. Normal signals are low and pulse high and inverted signals are high and pulse low.
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