Should I write camera motion in a prompt as degrees and percentages or as comparative language, and how do I match motion across a cut (Hailuo guidance)?

Problem. Two generated clips may not match in motion direction or speed at the cut. Conditions. I2V clips of about 4-6 s; vendor knowledge page (July 2026). Vendor guidance. (1) Do not use numeric camera commands such as 'Pan 30 degrees left' or 'Zoom 15%'; the page says these typically give inconsistent outputs and that the model interprets visual relationships and 'feel'. (2) Treat shot A as the master motion reference and prompt shot B comparatively: 'Continue the slow, deliberate dolly-in from the previous shot, maintaining the same forward momentum.' (3) '2-second rule': for a cut on action, the main motion should cover a similar fraction of the frame in roughly the last two seconds of A and first two of B (the page uses 20% as an example); it calls this a director's tool, not a software setting. (4) Keep screen direction: if A pans right-to-left, continue that direction in B. (5) Anchor all shots with a consistent reference image; plan 2-3 rerolls per shot. Evidence quality. The page states it is a scenario model based on internal studio heuristics, not a controlled lab study. Contrast with pose-conditioned models, where numeric trajectories are legitimate inputs (C3-B571-10). Limitations. No test data; applies to text-prompted I2V only. Version/date. Fetched 2026-10-23. Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Limitations: Vendor heuristics; the 2-second figure and 20% example are not validated. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "https://hailuoai.video/pages/knowledge/trajectory-matching-seamless-ai-video-cuts",
      "note": "Physics of Motion; Adjectival Pathing; 2-Second Rule; Maintaining the 180-Degree Rule; Method and Assumptions"
    }
  ]
}