Drzach & Suchy’s shadow cloud is a three-dimensional object, consisting of multiple shadow-casting elements semi-randomly arranged in three dimensions.
A shadow cloud can be viewed as a generalization of shadow casting panels, but of course the basic idea is already present in the so called GEB-triples.
*Drzach / architect, works in Basel / studied at ETH Zurich and at GSD Harvard University / worked in New York, Berlin, Zurich and Basel / combines art and design / creates furniture and portable display spaces
*Suchy / cryptographer, software engineer, works in Zurich / studied at ETH Zurich and at Carnegie Mellon University, / worked in Zurich, Pittsburgh PA, and New Brunswick NJ / experiments with holograms and Fourier transforms
A shadow cloud is a three-dimensional object, consisting of multiple shadow-casting elements semi-randomly arranged in three dimensions in such a way, that depending on the direction of illumination the overall shadow of the cloud displays various images encoded in it. A shadow cloud can be viewed as a generalization of shadow casting panels, but of course the basic idea of multiple shadows from one three-dimensional structure is already present in well-known GEB-triples. However, in contrast to GEB-triplets, a shadow cloud can encode up to four arbitrary images and display them under appropriate illumination without any distortions.
The idea of shadow clouds can be summarized as follows: the shadow cast by flat, thin elements depends on their relation to the direction of illumination: elements perpendicular to illumination cast clear shadows, while the shadows of elements parallel to illumination are practically invisible. Moreover, the elements perpendicular to the illumination can be arbitrary shifted along the illumination without changing the overall shadow cast by all the elements. This allows for a random, cloud-like placement of elements in space.
In a real, physical realization of a shadow cloud the floating elements must be somehow kept together at appropriate locations. One obvious way of achieving this could via a solid transparent material, like plexiglas. Another option is the use of a scaffolding, which allows for much larger and lighter installations with greater flexibility, and offers a different look-and-feel.
The rectangular grid as described above allows for encoding of three independent images. For encoding of four images we use a hexagonal grid and shadow casting elements with a more complex structure, as shown in Figure 3. See the video for an animated presentation of shadow clouds.
Shadow Casting Panels
Based on a technique and process described later in this post, Drzach & Suchy have created Shadow Casting Panels that that appear as one image in the morning light and another in the evening light. With some clever image choices like Marilyn Monroe becoming Marilyn Manson, it’s evolving art that can be used as installations or wall art of several types.
Multiple images are encoded within a single physical object — a white panel, which displays the separate images under appropriate lighting conditions. The underlying principle of our technique is based on a simple observation: the shadow cast by an object depends not only on the object itself, but also on the light; therefore the same object under changing lighting conditions can totally change its appearance.
The technique of encoding multiple images in a panel, so that single images become visible under varying illumination (so-called Shadow Casting Panels), was invented by Drzach in 2004 (patent pending), and then developed further by Drzach & Suchy.