We are planning to do a experiment which involves measuring pupil size of human subjects using an eye-tracker. The subjects will sit still during the experiment.
I wish to know what kind of eye-tracking devices gives more accurate pupil-size measurement, eye-tracking glasses or desktop eye-tracker? I know eye-tracking glasses gives relatively lower accuracy on fixation points compared to desktop eye-tracker, but what about pupil size? Pupil size changes slower, and eye-tracking glasses have cameras closer to the eye, and may provide better measurement.
Our lab currently has a SMI-ETG-2w eye-tracking glasses with 60 Hz sampling rate, and we don't have a desktop eye-tracker yet.