The best way would be to render to a series of still images (one of the Make Movie options). You can then composit those in a video editing program. You'll have far more choice in codecs and quality settings then.
Another advantage of rendering to still images is that in case Poser crashes - which will definitely happen one day or another - you don't have to rerender the entire animation, because all the finished stills (frames) are still there.

The pen is mightier than the sword. But if you literally want to have some impact, use a typewriter

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