Since with moving mirror lights the only thing that moved was the mirror, you could make the fixture's body as big as it needed to be, without needing to worry about making those components robust enough to survive a life in constant motion. This meant that many innovations in moving lights were actually seen first in these 'scanner' fixtures.
Martin's RoboScan Pro 518 is an example: this 250W scanner featured a mechanical dimmer, a prism, a choice of 14 colours and something quite new: a five-position gobo wheel where you could not just change the gobos, but make them rotate as well! Very soon, everyone else's lights could do the same thing!
Martin would repeat the trick a few years later with its much bigger PAL 1200 moving mirror light, the enormous body of which housed the first automated framing shutter system in a moving light - again, soon seen everywhere.

Roboscan Pro 518
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