In the 1990s, a war raged between two entirely different ways of moving a light: whether you moved the entire fixture, or you kept the fixture still and just moved a mirror attached to the front – which, being small and lightweight, could move really, really fast if required!
 
For some reason, moving mirror lights have largely fallen out of favour, but for a long time they were the first to introduce new features because there was no real penalty to enlarging their bodies to fit in more mechanics1; features like CMY colour mixing or rotating gobos appeared in these fixtures first. In the case of Martin’s PAL1200, perhaps the apex of the moving mirror era, there was all that plus zoom optics and, particularly, the first remotely controllable framing shutter system, each blade individually adjustable or the whole assembly rotatable just as now. Didn’t need shutters? The light was modular, so you just pulled them out and replaced them with something else. 
 
It was a big light but a versatile one – on Martin Guerre in 1996 linked up to the Wybron Autopilot system and so able to automatically follow scenery or performers. 

Martin PAL1200
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