The zoom level is dependent on the size of the comp. Larger comps cannot be zoomed as much as smaller ones.
There’s probably a maximum size for the CompSize * Zoom; it seems to be 32,000 pixels in any one dimension. (In other words, you can do a comp 7999 pixels wide at 400%, but not a comp 8000 pixels wide).
Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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