July 2003, a junior high school in Shimane, Japan: 294 first-years watched a 20-minute class video on a big screen in a lecture hall. It was shot handheld, full of sudden pans, tilts, rolls and zooms. About 50 felt sick, with nausea, cold sweat and headaches, and 36 were taken to hospital. The erratic camera movement is thought to be the cause; the worst cases sat at the front and in the middle.

Japan's national research lab, AIST, rebuilt the shake in a virtual room. What mattered most wasn't how often the picture moved, but how fast. A steady turn was worst between 30 and 70 degrees a second. That work led to international guidance on image safety; today's standard is ISO 9241-394 (2020).

A phone covers far less of your view. Nobody has tested whether that protects you. This film's own shake never turns faster than 22 degrees a second.

Did your stomach notice anyway?

Sources: Ujike, Synthesiology, AIST (2012); Ujike, Ukai and Nihei, Displays (2008); Ujike, Proceedings of VIMS2007 (2007); Solimini et al., Italian Journal of Public Health (2011); ISO 9241-394 (2020).
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