Thank you. The “crop” node doesn’t have any apparent effect. I still have only a dozen green (playable) frames at any one time. As Resolve calculates the next one, the green line starts eliminating frames from its beginning, keeping the playable range extremely short. This make rendering out from Fusion unfeasable because I can’t even see what my output will look like (I’m talking about a 10-second simple zoom here…) Playback is at 2.3 frames/sec and memory never goes above 50%.
BTW, if I use the exact same image file and just put it on a 1920×1080 timeline and turn on Dynamic Zoom, it plays silky smooth. But that option gives me very little control on keyframes. So it’s not a memory/graphics problem it seems.