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FAQ: What do the threshold bias values (e.g. "x1.00") mean in remote mode?
#1
In Remote mode, the Host software automatically adjusts the pupil and corneal reflection (CR) thresholds in real-time. This is necessary to compensate for changes in brightness as the participant's head moves closer to or further from the camera. Because of this, the manual threshold adjustments do not set an absolute value. Instead, they adjust a bias that influences the automatic adjustment range.

Use the same keys as in Head-Stabilized mode to make adjustments:
  • Pupil Bias: ↑ and ↓ arrow keys
  • CR Bias: + and - keys
As a general rule, you should aim for bias values between 0.9 and 1.1, with a value as close to 1.0 as possible.

Testing and Troubleshooting
After setting the bias, have the participant slowly look at the four corners of the display screen. Watch the Host PC monitor and ensure the CR is not lost.

If the system loses the corneal reflection, a red "No CR" warning will appear. If this happens, some small, further adjustments to the bias values will usually restore tracking.


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