Anamorphic and Box Tunnel Content Explained

How box and tunnel illusions are constructed, what the geometry requires, and why they photograph better than they are experienced.

The box and the tunnel are the two configurations where a wrapped screen can produce a genuine spatial illusion. A box, where screens meet at a corner or enclose three sides, can appear to contain a volume. A tunnel, where the screens surround the viewer overhead and to both sides, can appear to extend the space they are walking through. Both are geometric constructions rather than visual effects.

The construction is forced perspective. The content is built as a three dimensional scene in a virtual space that corresponds to the real one, and then rendered from a defined viewpoint. Where two screen planes meet, the geometry is deliberately distorted so that from that viewpoint the corner disappears and the virtual space appears continuous with the real one.

The consequence that clients find hardest to accept is that the illusion is correct from one position. At the design viewpoint it is convincing. Well off axis, the distortion is visible as distortion. This is why these installations circulate as recordings: a camera on a tripod at the sweet spot preserves the one correct view, while a person standing to the side saw something considerably less impressive.

For a tunnel the position problem is different and more forgiving, because a tunnel has a natural viewing axis. Anyone walking through it is approximately where the design assumed, which is why tunnel installations tend to work better in practice than corner boxes in open rooms. The trade is that the viewer is moving, so the content has to hold up across a range of positions along the axis rather than at a single point.

The technical requirements are unforgiving and must be confirmed before design. Exact pixel dimensions of each plane, physical dimensions in metres, the angles between planes, the height above the floor, the position and height of the design viewpoint or the walking axis, and whether the planes are truly flat. Small errors produce a visible break at the join, which destroys the effect rather than degrading it.

Content design has its own logic. The illusion is strongest when the virtual object or space appears to extend away from or toward the viewer through the join, and weakest when things move parallel to the screen. Simple, readable forms work better than complex geometry, because complexity gives the eye more opportunities to detect the distortion. Real world scale cues strengthen the effect substantially.

Text should not participate in the illusion. Reading is a flat activity, and text rendered in forced perspective is either distorted or breaks the spatial reading. The convention that works is to hold text on a single plane, presented conventionally, and to reserve the dimensional treatment for the imagery.

The perceptual basis for why these work commercially is the same as for other immersive formats. Poushneh (2021) found that perceived proximity to a virtual product influenced purchase intention, and an anamorphic reveal produces an unusually strong sense of proximity because the object appears to enter the viewer's physical space. Johnson Jorgensen and Sorensen (2026) similarly documented that dimensional presentation shapes product perception.

The production reality is that this is 3D work rather than video work. The scene has to be built, the virtual camera placed at the design viewpoint, and the render performed with the screen geometry accounted for. Generated material can contribute textures and environments within the scene and cannot produce the effect, because the effect is a geometric construction.

The practical recommendation is to treat these as designed moments rather than running formats. A short, well built illusion at the entrance, at the product reveal or at the photograph point delivers the effect and the shareable recording. An entire evening of anamorphic content costs a great deal and delivers the illusion to a fraction of the audience for a fraction of the time, which is a poor return on the most technically demanding content a studio can produce.

References

Poushneh, A. (2021). How close do we feel to virtual product to make a purchase decision? Impact of perceived proximity to virtual product and temporal purchase intention. Journal of Retailing and Consumer Services, 63, Article 102717. https://doi.org/10.1016/j.jretconser.2021.102717

Johnson Jorgensen, J., & Sorensen, K. (2026). Millennial perceptions of augmented reality in retail. Virtual Worlds, 5(3), Article 30. https://doi.org/10.3390/virtualworlds5030030