I’m using more than 20 images of all different sizes, but the four TIFs that were giving me problems were 1450×1161, 2000×1427, 2000×1450 and 2000×1244.
Here’s the thing- I have used other TIFs and JPEGs of a similar size with a fair amount of keyframing and filtering, and though they take forever to render, they’ve worked just fine.
I suppose I should just work them in Motion…