4:3 presentation background: 10 seconds on Seedance 2.5, $5.82

A 10-second 4:3 clip at 720p on Seedance 2.5 renders at 1112 x 834 pixels and costs $5.82 on Sume. Requesting 4:3 directly means the clip already fits a 4:3 slide, with no letterbox bars and no crop that cuts off the subject.

Compare it with 16:9 at the same length and resolution: $5.78. The 4:3 frame has fewer pixels, so the clip is cheaper.

4:3 by resolution, 10 seconds

Making it behind-text friendly

Ask for slow, low-contrast motion (drifting light, soft gradients) so text stays readable on top. A background does not need audio: set generate_audio to false, which does not change the price.

Seedance 2.5 on Sume has no seed and no looping control. To make a loop, use the same image as first and last frame, as in the plant-shop post in this series, and check the join.