Argus Science ETVision Instruction Manual Download

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E T V I S I O N M A N U A L

6.6.6

Manual offset correction

If,  sometime  after  subject  calibration,  gaze  data  appear  to  be  in  error  by  a  constant  amount,  for
example always slightly to the right of the object being fixated, this can be corrected without repeating
the calibration process.  Such an offset error might be caused by a significant change in pupil diameter
after calibration.

On the

Data Display

window, click the button labeled “Drag Left Mouse Button to Adjust”. The

button will remain depressed (feature is “on”) until clicked again. Ask the subject to look at some
landmark on the scene image, and use the left mouse button to drag the mouse arrow in the “POG
Display” area of the

Data Display Screen

. The POG cursor on the

Data Display Screen

, as well as

the

Scene Image

window will be offset in the direction and by the amount that the mouse is dragged.

Drag  the  POG  cursor  to  the  point  in  the  scene  image  being  fixated  by  the  subject.    The  offset
correction  can  be  reset  to  zero,  while  the  “Drag  Left  Mouse  Button  to  Adjust”  feature  is  on,  by
dragging the mouse in the “POG Display” area with the right mouse button depressed.  Offsets are
automatically re-set to zero whenever a subject calibration is performed.

Note that when the “Drag Left Mouse Button to Adjust” feature is on, the mouse cannot be used to
adjust the scale and origin of the “POG Display” area graphics. These capabilities are restored when
the “Drag Left Mouse Button to Adjust” feature turned off.

To disable the “Drag Left Mouse Button to Adjust” function (turn the feature “off”), and protect
against accidentally creating offsets, click the button to un-depress it.

The Manual offset correction feature can be used even while recording data on ETVision, as described
in section 6.7.1.

6.6.7

Monitor Battery Charge

When the battery charge level drops below 15%, the battery LED on the Controller will turn red. If
this LED turns red, or if the battery indicator on the

ETVision

PC application shows less than 15%

battery  charge,  it  is  recommended  that  either  the  power  supply  be  connected  to  the  Controller  and
plugged  into  AC  power,  or  alternately  that  any  opened  data  files  be  closed  and  the  Controller  be
recharged as described in a previous section.  If the battery charge drops significantly below 15% the
voltage may become too low for proper operation and the system will automatically shut down.

6.6.8

Audio

Audio picked up by the microphone in the optics frame can be heard, if desired, on the

ETVision

speakers. If headphones are connected to the

ETVision

Controller, audio picked up by the PC

microphone can be sent to the headphones.  These features can be individually enabled or disabled,
and  may  be  very  useful  in  environments  where  the  participant  and  the  equipment  operator  cannot
easily hear each other directly.

The

ETVision

PC microphone and speaker are enabled or disabled from the “Video Source” dialog on

the

System Control Table

window. Click the “System Control Table” icon, on the

ETVision

menu bar

to open the

System Control Table

window, then select the “Video Source” tab. The speaker symbol