Sounds like a Shack-Hartmann wavefront sensor, just being measured many times throughout the exposure: https://en.wikipedia.org/wiki/Shack–Hartmann_wavefront_se

Sounds like a Shack-Hartmann wavefront sensor, just being measured many times throughout the exposure: https://en.wikipedia.org/wiki/Shack–Hartmann_wavefront_sensor https://en.wikipedia.org/wiki/Shack–Hartmann_wavefront_senso...