When Is A Hologram Actually A Hologram? Mostly Never!
There's been a great deal of activity in event technology circles involving holograms and holographic techniques. Some of this activity has made big waves and created a lot of excitement, which is good for business, particularly if you're in the business of supplying the technology that supports these installations.
However, it's interesting to note that these "hologram" displays have little in common with holograms or holographic technology. The term, as it's currently being used, is a misnomer and is a closer relation to the "Pepper's Ghost" effect that's been in use for quite some time.
The question for you, event producer or brand manager, is whether this is a good trick for you to use or whether the trick will end up being on you. For help, read on:
The ghost technique requires that a reflection appear on a transparent surface, which is not as easy as it might sound since a truly transparent medium won't show a reflection - the light will simply pass through the surface. This effect uses a material that appears transparent, allowing the viewer to see all objects in the space as if there was nothing there, while allowing the reflection to appear with as much detail and brightness as possible. The reflection is typically supplied by a video projection or video display arranged so that the device is hidden from the viewer. We do not want the viewer to see the technology or it ruins the effect.
To accomplish the reflection feat, a thin piece of treated glass such as partially silvered mirror can work for smaller image areas, while large installations will require the specialized foil that's been used for the past decade or so, including the now famous posthumous appearance by a well-known rap artist at a music festival in Southern California. Given the right environment and the right content, the "ghost" trick can be an absolute stunner, but in a less ideal setting the ghost spirits will take their revenge in the form of high cost and low return.
The biggest obstacle to the effectiveness of this trick is the quality of the audience viewpoint. If the audience can see the trick clearly from up close, you have a challenge on your hands. If the audience is at a considerable distance (such as an audience at a music festival), or is viewing the scene in a restricted manner (such as through a window), or in a space with very carefully controlled lighting, the chance of success grows considerably.
The issue related to close-up viewing is that the technique creates an image lacking in contrast and detail, and since it is displayed on a single plane and is not truly three-dimensional (also called volumetric), the illusion is risked by funky image quality and the visibility of the screen element. That means no dust or dirt on the screen and no air movement that might make the thin film vibrate.
Of course, really creative, fun content will make most audiences overlook any technical shortcomings. Plus there are some alternatives that may support the illusion but are less exotic, and therefore, have lower cost and risk. For example, current LED tiles that feature very high-resolution and super-black image surfaces will disappear from view in a dark space when no image is present. However, when the image appears, it will be brighter, more colorful, and more lifelike than what can be attained using the ghost projection technique.
Using LED tiles for this application requires careful design of content, staging, and lighting, but it can be a less complicated alternative to the effect described above. For design and technical information on using high-resolution LED tiles to support your next séance, call your WorldStage account exec or email us at firstname.lastname@example.org.