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An EyeLink Portable Duo Tutorial: Running an Experiment
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2016-2017 SR Research Ltd.
camera can be found in section 4.1 “Installing the Eye Tracker on the Laptop
Mount” of the EyeLink Portable Duo Installation Guide).
1)
Please make sure you use a height-adjustable chair so that you can
raise/lower the participant to the appropriate height. When the subject is
seated, tilt the screen of the laptop so that it is perpendicular to the
participant’s line of sight.
2)
Place the Laptop Mount over the keyboard area of the laptop with the two
side rails resting on the edges of the laptop. You can slide the mount forward
if the camera is blocking the participant’s view at the bottom of the screen;
otherwise, the camera should be placed as close to the screen as possible
without blocking the participant’s view. Adjust the position of the laptop so
that the eye tracker is placed at a distance of about 45 cm if measuring from
the front of the unit to the participant's eyes. The camera is recessed about 7
cm behind the front of the enclosure, and the ideal eye-to-camera distance is
about 52 cm. Please measure the screen dimensions and viewing distance
and update screen settings for the tracker (see section 5.4 of the EyeLink
Portable Duo Installation Guide).
3)
Start the EyeLink Host PC application. Check whether it displays “Head-
Stabilized” at the top of the Setup screen. If not, click the “Operating Mode”
panel in the top-left corner of the screen and choose the “Head-Stabilized”
Mode.
4)
After the participant is seated, check the camera image displayed on the Host
PC. If the participant’s eye image is not displayed in the vertical center of the
camera view, adjust the camera angle by loosening the clamping knob on the
right side of the mount, holding the camera with your left hand and tilting it
to the intended angle, and then tightening the clamping knob to keep the
camera at the intended position. Adjust the angle/position of the laptop if the
participant’s eyes are not displayed in the horizontal center of the camera
view. If both eyes are tracked, a dotted vertical line is drawn in the camera
image to represent the hemifields in which the left and right eyes will appear;
make sure the dotted line is between the two eyes.
If you have the eye tracker mounted on a tripod (see section “3.1 Mounting the
Eye Tracker on the Tripod” of the EyeLink Portable Duo Installation Guide for
mounting instructions), please take the following steps to set up the eye
tracker.
1)
The Display PC monitor should be set such that when the participants are
seated and looking straight ahead, their eyes are level with the top 25% of
the monitor.
