A very slow zoom in tightens the frame before the audience notices. It creates a pressure, as if something is approaching.
When a character doesn't know about the danger yet, when showing an empty room, a door, or a photo for a long time.
Official preset available — Higgsfield 'Zoom In', Veo 'Zoom (in/out)' (for example: slow zoom in on a mysterious artifact). The Melies 'Slow Zoom In' page also has a prompt example.
Extremely slow creeping zoom in on an old rocking chair that moves gently by itself on a moonlit porch, barely noticeable at first, camera position fixed, 50-200mm zoom lens, cold blue light, unsettling silent mood, 8-second shot.
very slow optical zoom in on an empty dark doorway at the end of the hallway, camera locked on a tripod, the zoom is almost imperceptible over the whole shot, silent house
Hereditary (2018) — Cinematographer Pawel Pogorzelski shot long from a distance and used many slow, careful pans and zooms (Queen Anne News review)
Higgsfield Motion: Zoom In Demo · Melies — Slow Zoom In Prompt