[throwaway22032]

I don't know about the Canon 1000D but almost all cameras I've used recently have electronic shutters.

There is a rolling shutter penalty so you wouldn't want to use it in the "real world" for moving subjects but if you synchronise it properly (e.g. move one physical frame, take photo, move one physical frame) and ensure that there is no movement during the exposure then this shouldn't make a difference.

Even the worst culprits like a 61MP mirrorless (huge overkill for this task) with ~100ms readout could trivially keep up with 22 shots per minute.

[_Microft]

They are advancing the film one frame at a time and are taking static images. There's a switch getting actuated that triggers image capture once the film has advanced. The first video in the article has close-ups of the process.