Ever wondered how super slow motion in the past was capable of multi-thousand fps performance with just film exposures? Well, they used customized camera rigs that combined multiple rolls of films, mirrors, and synch cables to essentially get a result beyond what the limitations of the equipment forced upon the shooter.
In a very cool video by Camera Tech on Youtube from 2015 they were able to get a custom mirror rig to shoot simultaneously on two GoPro cameras with a semi-translucent angled mirror that splits the light to each camera lens by 50% making it possible to sum both frame rates in post by alternating the frames captured by both cameras with a very slight time difference equivalent to 1/frame rate expected.
