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Original comparison of rainbow-hologram viewing: two side-by-side views of a generic sphere show horizontal parallax, while vertically stacked views change from red to green to blue without adding a new vertical perspective.
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Find Sphere in the 1975 exhibition catalogue (PDF) ↗

Holography & tricky projections / 1968 · white-light transmission holography

Rainbow holography — Benton’s Sphere

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A hologram becomes visible in ordinary white light. Move sideways to explore depth; move vertically and its colour changes through the spectrum.

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Find Sphere in the Museum of Holography’s 1975 exhibition catalogue, then compare the two directions in the diagram. In a rainbow hologram, sideways movement changes perspective; vertical movement mainly changes colour. Look for a similar effect in a holographic foil on a card or package.

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THE IMAGE IN THIS ARCHIVE

Through Mirror · original explanatory diagram

Original file & attribution · CC0 1.0

Original explanatory diagram created for Through Mirror. It illustrates the optical principle and is not a photograph of a performance or installation. Gallery previews may be resized or converted to WebP; animated previews show the first frame.

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Frequently asked questions

What is Rainbow holography — Benton’s Sphere?

A hologram becomes visible in ordinary white light. Move sideways to explore depth; move vertically and its colour changes through the spectrum.

What should I look for in Rainbow holography — Benton’s Sphere?

Find Sphere in the Museum of Holography’s 1975 exhibition catalogue, then compare the two directions in the diagram. In a rainbow hologram, sideways movement changes perspective; vertical movement mainly changes colour. Look for a similar effect in a holographic foil on a card or package.

What explains Rainbow holography — Benton’s Sphere?

A rainbow hologram is transferred from a master using a narrow horizontal slit. The slit preserves side-to-side perspective while restricting vertical parallax, reducing the blur that white-light reconstruction would otherwise produce. Different wavelengths emerge at different vertical angles. Moving your eyes up or down selects a different spectral colour; moving sideways still reveals different views of the object.

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Original two-panel diagram showing an object wave and reference wave meeting at a holographic plate, then a developed transmission hologram reconstructing a virtual object for a viewer on its opposite side.

Transmission holography — Optical Interactions

Gary Fisher · Optical Interactions

A flat glass plate reconstructs light from a still life. Move sideways and the objects reveal a different view, as though you were looking through a window.

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Original reflection-hologram diagram showing a lamp and viewer on the same side of a plate, with selected light returning to the viewer and dashed extensions locating a virtual image behind the plate.

Reflection holography — Cassadaga (Spirit Pond)

Matthew Schreiber · Cassadaga (Spirit Pond)

A lamp illuminates a flat plate and an image appears to occupy depth. The light returns towards the viewer from a recorded structure inside the holographic material.

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Original plan-view diagram of Pepper’s Ghost: a hidden figure is reflected in angled glass, appearing as a virtual figure on the visible stage.

Pepper’s Ghost

Henry Dircks and John Henry Pepper

A figure appears on an empty stage, transparent enough for the scenery to show through. Its real source is hidden elsewhere.

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Original comparison of rainbow-hologram viewing: two side-by-side views of a generic sphere show horizontal parallax, while vertically stacked views change from red to green to blue without adding a new vertical perspective.

Rainbow holography — Benton’s Sphere