The kronoscope: a window into the past

How to display the buildings that once stood on these ruins is an old and still undecided debate among archaeologists. A painting, a model locked away in a glass cabinet or a computer animation on a screen are all detached from the scene itself. The scale and perspective are different. What about rebuilding? Although they use this technique in many places, it is very expensive and a professionally risky undertaking. No one guarantees credibility! Where are the original materials and techniques today? And a bad reconstruction will cover the remaining, original ruins as well. Nevertheless, the demand is huge, tourists visiting fields of ruins are not satisfied with knee-high walls, and they are unable to imagine the old buildings just from them.
The developers of the kronoscope made use of the technology of virtual reality. Visitors can walk around a park of ruins; stop at a kronoscope installed at a suitable location and look into the instrument. Through the viewer standing on its shiny metal post you can scan all the way round like a periscope and look into a reconstruction of the past.

The past mingles with the present and the reconstruction with reality in the three-dimensional image you see. You can see everything in its proper place, size and distance; it is as if it had really been built. You no longer have to imagine it; it is standing there before you. And the latest model even enables movement: full-motion video with sound effects and narration in several languages is made possible while looking round up to 360 degrees!

The method is not only suitable for resurrecting ruined buildings; it can even display entire cityscapes. How exciting would it be for a tourist to look around Budapest at the end of the 19th century, or the medieval main square in Esztergom with a kronoscope? Or in the future: let’s show inhabitants how a projected building will fit into the existing environment!
The kronoscope itself is a Hungarian invention under Hungarian and, shortly, European patent protection. The heart of the device is a self-adjusting image display mechanism that can be rotated through 360 degrees, which always displays the part of the virtual image falling in the given viewing direction. The wide-angle (40°x40°), light intensity image you see through the viewfinder enables to see fine of details. The design is the work of Tamás Hurton. The housing can withstand all weather conditions: rain, hot sunshine and frost. By holding the two handles on either side you can easily turn the device and the 3-level platforms make it comfortable to use for both adults and children as you do not have to bend over or stand on tiptoe. By looking away from the spectacle seen in the kronoscope you can compare it with the present-day environment and precisely identify what the individual ruins looked like in their original state.

Naturally, the image displayed in the kronoscope is created by a computer, using state-of-the-art 3D modelling. The work always starts by drawing up theoretical reconstructions. Expert architects determine how the building looked in its original condition using the present ruins, any period depictions available and analogies drawn from buildings that are still standing today. The theoretical reconstructions of Diósgyőr Castle are the work of architect György Szekér, official at the National Office of Cultural Heritage, and the reconstructions of Kisnána Castle were elaborated by Visegrád chief archaeologist Gergely Buzás.
The theoretical building reconstructions in Aquincum’s first two kronoscopes are archaeologically authentic and were created by the late professor dr. Gyula Istvánfi of the Department of History of Architecture and Monuments of the Budapest University of Technology.