Why it happens
- The costume is described generically, like “uniform”, with no colour, material or accessories.
- There is no prop-state sheet, so nobody knows where a prop should be or what state it's in per scene.
- Keyframes were generated in batches and the reference image or model changed partway through.
How to fix it
Write costume colour, material and every accessory into the character's fixed description.
Keep a state sheet for each story prop: size, colour, who holds it, and how it changes after each scene.
Before generating a keyframe, compare it item by item with the previous shot's last frame.
When something doesn't match, redo the keyframe only; don't carry the error into video generation.
Before and after
Fails
She wears a uniform and holds a delivery bag.
Works
She wears a grey-blue cotton uniform, a thin orange tie and a silver badge on the left chest; in her right hand, a white plastic delivery bag tied at the top.
Prevent it next time：Put costumes in the fixed description and props on a state sheet, and check both before every shot.
Worked examples
Keep one character's face stable across 6 shots
A character's face and features change as shots move between wide, close-up and profile.
→Control a location change with first and last frames
A walk from inside to outside morphs the set midway and doesn't end on the frame you wanted.
→Keep period costume and hairstyles consistent
A period character's topknot, hairpin, collar and embroidery differ from shot to shot.
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