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from the last calibration is cleared, and the process starts “from scratch” (as though no subject
calibration has ever been done).
Although calibration points can be entered in any order, it is recommended that the first be near
horizontal center of the scene camera image, and at or slightly below vertical center. This will usually
ensure that the pupils and all CRs can be properly recognized at this point. It is further recommended
that additional points be added as described in section 6.5 since that sequence will most likely show
progressive POG accuracy improvement as each additional point is added. Ultimately, a set of points
in given locations will yield the same final result no matter the order in which they are entered.
A 9 point value for “Total Calibration Points” allows for the maximum number of points that are
likely to make sense before “diminishing returns” set in.
