Setup: Premiere pro 15.4, imac mini 16gb m1 bigsur 11.4, 4k prores footage from a sony a7r3 shot with a ninjaV, editing on a 1080p timeline.
Using keyframes on an adjustment layer to create a motion blurred zoom into my 4k footage that is set to frame size, ive noticed that the effect degrades my image’s sharpness as compared to when the 4k image is just dropped on the 1080p timeline when not set to frame size with no zoom in effect. I thought it was just the youtuber preset i used, but the same thing happens even when just doing a manual simple zoom in with no motion blur without the preset. Ive tried everything but revert back to an older version of premiere and am close to my wits end. What is the issue? Here is a video link example: https://youtu.be/oZ31fuGqbj8 help would be greatly appreciated!!
I don't know what the preset is, but can you try it with no adjustment layer. Set to Frame Size, which should set your scale at 50% then zoom in using the clip controls anything up to 100% scale, the quality should remain the same.