Eye tracking white sclera (limbus tracking). It presents another challenge for vertical eye movements due to obstruction of eyelids. Eye-tracking setups vary greatly: some are head-mounted, some require the head to be stable (for example, with a chin rest), and some function remotely and automatically track the head during motion. Most use a sampling rate of at least 30 Hz. Although 50/60 Hz is more common, today many video-based eye trackers run at 240, 350 or even 1000/1250 Hz, speeds needed in order to capture fixational eye movements or correctly measure saccade dynamics. Eye movements are typically divided into fixations and saccades
Eye of the Stalker well as a video of Beth. When Stephen attempts to break into her home one night, Liz sets out to locate Beth after recognizing her from the video. They both join forces to catch Stephen in the act, using Beth as bait. Liz gives Beth a loaded gun, which the latter eventually uses when she sees Stephen holding Martha and threatening to slit her throat with a knife. Beth fires a warning shot to deter Stephen, and he is finally arrested. Eye of the Stalker Eye of the Stalker (a.k.a. Moment of Truth: Eye of the Stalker and Eye of