A virtual tour is a simulation of an existing location, usually composed of a sequence of videos or still images. It may also use other multimedia elements such as sound effects, music, narration, and text. It is distinguished from the use of live television to affect Tele-Tourist
The phrase "virtual tour" is often used to describe a variety of videos and photographic-based media. Panorama indica
tes an unbroken view, since a panorama can be either a series of photographs or panning video footage. However, the phrases "panoramic tour" and "virtual tour" have mostly been associated with virtual tours created using still cameras. Such virtual tours are made up of a number of shots taken from a single vantage point. The camera and lens are rotated around what is referred to as a no parallax point (the exact point at the back of the lens where the light converges). Unlike the virtual tour's static wrap-around feel, a video tour is a linear walk-through of a location. Using a video camera, the location is filmed at a walking pace while moving continuously from one point to another throughout the subject location.[ citation needed ] 3D virtual tours can be created using 3D reconstruction. The origin of the term 'virtual tour' dates to 1994. The first example of a virtual tour was a museum visitor interpretive tour, consisting of 'walk-through' of a 3D reconstruction of Dudley Castle in England as it was in 1550. This consisted of a computer controlled laserdisc based system designed by British-based engineer Colin Johnson. One of the first users of a virtual tour was Queen Elizabeth II, when she officially opened the visitor centre in June 1994. Because the Queen's officials had requested titles, descriptions and instructions of all activities, the system was named and described as: "Virtual Tour, being a cross between Virtual Reality and Royal Tour." Details of the original project can be viewed online. The system was featured in a conference held by the British Museum in November 1994 and in a subsequent technical paper. Virtual walk videos are documentary motion pictures shot as the camera continuously moves forward through an urban or natural area. The effect is to allow viewers to experience the sights they would see and the sounds they would hear were they actually traveling along a particular route at the same pace as the camera. Virtual walks based on real-world photography typically do not require the use of virtual reality goggles or headsets of the kind used by gamers. In realistically simulating the experience of moving through space, virtual walks—or virtual runs or bicycle rides—differ from conventional travel videos, which typically consist of a sequence of mostly static camera setups along a particular route or within a given area. The advantage of the conventional travel video is that one or more narrators or on-screen guides can provide insights into the geographical, historical, political, military, cultural, geological, or architectural aspects of the area. Virtual walks appeal to those who want to experience the sights and sounds of particular places in the country or the world, but who may not have the time or the financial or physical resources to actually travel there. They also appeal to treadmill or elliptical trainer users, for whom walking or running while watching these videos enhances the reality of the experience (and, at a minimum, reduce the boredom of the exercise). Some feature-length narrative motion pictures have made use of the virtual walk technique for dramatic purposes. These include the opening sequences of Orson Welles’ Touch of Evil and Robert Altman's The Player, the famous tracking shot through the Copacabana in Martin Scorcese's Goodfellas, Alexander Sokurov's Russian Ark (which consists of a single 96-minute Steadicam take), and, more recently Alfonso Cuarón's long tracking shots in Gravity, and almost the entire narrative structure of Alejandro Gonzáles Iñárrito's Birdman.