Virtual reality for everyone?
There has been an immense amount of media attention (particularly in the computer press) surrounding Apple Computers' ground-breaking virtual reality technology, QuickTime VR.
The concept behind QuickTime VR is straightforward: a series of photographs taken from a set camera position separated by a fixed angle are 'stitched' together to form a single panoramic image. This image is then wrapped inside a cylinder so that when a cursor is moved within the image it gives the impression that you are actually looking within the space.
As well as using photographs to create your VR scene, you may also, in many applications, save rendered scenes in a suitable format. The beauty of using a virtual camera (as opposed to dealing with the constraints of lens and camera) is that the panoramic image can be taken with just one 'photo'.
But is it possible to fuse the photographic technology with a rendered computer model? Following the completion of a 'standard' computer montage for John Sell of Sell Wade Postins, we decided to push the technology by rephotographing the site in VR format and then montaging into it the rendered VR scene
Step one involves taking 12 photographs at 30degrees apart. The photographs were taken with a standard 35mm camera but with a wider than normal lens (18mm in this case), using standard film but scanning the negatives digitally. The camera is mounted on a panoramic head that rotates the camera at exactly 30degrees and positions the nodal centre of the lens over its rotation point.
The images are then stitched together to form a single panoramic image. We used Apple's QuickTime VR Authoring Studio on the Macintosh and then Live Pictures PhotoVista/ Reality Studio) to create the finished VR movie.
The next stage is to create a computer model of the scene and render it photorealistically in VR format. For this we used MiniCAD and ArtEPSILONlantis to create a CAD-accurate 3D model, then rendered it in a VR format.
The final stage is to montage the rendered with the real. For this we used the standard in image manipulation software: PhotoShop.
The final result is a single 'node' VR movie with the building in context which can fit on to a floppy disk, and be incorporated on to a multimedia CD/presentation with other nodes that can give a complete tour of the street and the building.
The files are also small enough to be quickly downloaded (using Java so there is no need to obtain a plug-in) from a website.
To view this example setyour browser to http://www.conVRgence.com/java/ajvr.htm
For VR photography, equipment and consultancy contact Mark Stephens at conVRgence, tel 0181 361 4175.
Gomark, UK distributor of MiniCAD and Artlantis, tel 0171 731 7930
Full-Moon Digital, UK distributor of Apple QTVR Authoring Studio and Kaidan panoramic heads, tel 01628 660242
Principal Distribution, UK distributors for Live Pictures PhotoVista and Reality Studio, tel:01756 704444