TechCrunch:
>A successful live-action Star Wars TV series is important in its own right, the way this particular show was made represents a far greater change, perhaps the most important since the green screen. The cutting edge tech (literally) behind “The Mandalorian” creates a new standard and paradigm for media — and the audience will be none the wiser.
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>What is this magical new technology? It’s an evolution of a technique that’s been in use for nearly a century in one form or another: displaying a live image behind the actors. The advance is not in the idea but the execution: a confluence of technologies that redefines “virtual production” and will empower a new generation of creators.

I’ll be the first to admit I found The Mandalorian boring and juvenile but the effects and visuals are spectacular. Be sure to also check out the much more detailed look into this in American Cinematographer Magazine.