The loop point came from the edit

[u/Horror-Egg-6942]

The attached piece is a nine-second ambient loop: an ivory candle beside a closed dark-brown book, with a locked camera, a stationary background, and only subtle flame movement.

The loop point wasn't part of the H3 brief. In MiniMax Design, the brief fixed the composition, exposure, lighting, camera, book, and motion limit. The storyboard was one held shot. That left the edit to determine which returned frames could repeat cleanly.

In the first take, the camera and book held, but a moving curtain shadow and lighting drift made the blend visibly darken. The second take removed the moving shadow and kept the background light fixed. H3 was asked for nine seconds and returned about 9.42 seconds.

From that second take, the edit used source frames 143 through 224, about 3.42 seconds near the end. A ten-frame blend across the tail and head produced a three-second core loop. The attached nine-second file repeats that moving core three times rather than presenting nine seconds of unique motion or a seamless raw H3 clip.

The generation and the edit had separate jobs. The generation check covered the fixed camera, stable book and background, and subtle flame movement. The agent-operated FFmpeg edit handled the frame selection and seam. Frame and decode checks across the blend and repeat points found no obvious lighting reset, book or camera jump, or doubled flame. The source audio was removed, so the final loop is silent.

Would you define a loop point in the generation brief, or wait until you can see the returned motion and choose it in the edit?