Maybe I'm misremembering the spy satellites using this (keeping the images secret is harder is you transmit them), but Lunar Orbiter 5 worked this way, so we had the technology in the 60's
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The lunar Orbiter used an adapted E-1 camera from SAMOS. The E-2 and (canceled) E-3 also used the semi-dry development process and photomultiplier readout method.
It would be interesting to know about the scan out piece here.
The idea makes sense to me, generally, in that film is high res, high speed, can have a fadt shutter. Given where digital computers & imaging were, the idea of turning digitization into a batch slow process decoupled from capture makes all the sense in the world.
[edit]
The lunar Orbiter used an adapted E-1 camera from SAMOS. The E-2 and (canceled) E-3 also used the semi-dry development process and photomultiplier readout method.