Weight and ease

Motion at one even speed reads as animation. Real things gather, travel and settle, and hair arrives after the head.

The physics rules are taught in Video with Seedance → Physics. Here is how they read as real, and how to check them [official guidance; hair, cream and skin have no top-creator source yet]:

• Every ordinary move gathers, travels and settles. Write the settle: "she sets the kettle down and the lid rattles once". Locked and dolly shots still get the settle on the landing.

• A walk has weight: heel contact, weight transfer, a hip shift. Never a glide.

• Hair is a material with weight: it lands a beat after the head, strands lag and settle one by one, and flyaways move for a reason.

• Every movement has a named physical cause [proven]: hair moves because of a named wind, a hand or a turn of the head (see Genres → Rules for every genre).

Check the speed by eye, frame by frame: each move should gather at its start and settle at its end. A video-analysis report can be asked whether moves gather, travel and settle, or run at one even speed (see The quality bar → Judging motion honestly).

Check the hair on the 1080p finish at 100%: step through the turn frame by frame. The mass should break into strands and arrive after the head.

Why: Higgsfield's guides say that motion carrying no weight reads as animated, and Luma names the failure "floaty": objects at one constant speed, with no acceleration and no slowing down.

Sources

• Higgsfield's realism guide and movement guide; Luma's realism guide.