Aerial Photography and Visualization

Recent books dealing with "visioning" and "visualization" have argued the need for presenting spatial issues to the general public. Both architects and planners have highly specialized, impenetrable jargon (related to stylistic issues in architecture and to zoning law in planning) which discourage public discussion. When architects and planners attempt to connect at public meetings or "charrettes" they often bring visual aids that help for an hour or two. Visual preference surveys are popular.(5) Scale models are great--but cumbersome, and expensive to build with detailed facades and movable parts. Hand-drawn bird's eye views (axonometric drawings), and digital programs that simulate them, can show development alternatives, but are limited in how real they seem. Technical staff are needed to draw and manipulate them. When practitioners go away, often the visualization tools go with them.

Aerial photography has not yet been developed in the United States as an important aid to citizen involvement in planning and preservation efforts because of its expense and inaccessibility. The technique began with wet-plate cameras used by photographers in hot air balloons in the mid-nineteenth century. They shot cities such as Paris and Boston, a dangerous trade if the balloons crashed. By World War I, aerial photography was tied to airplanes as a military reconnaissance tool.(6) By the later twentieth century, that reconnaissance model was applied to land surveys. A fixed camera in a plane flying at a single altitude would shoot large, high resolution 9 by 9 negatives in black and white. These were taken at 90 degrees to the ground, and were not easy to read. This was always an expensive format as well as a rigid one, and any shift to color photography only increased the expense of reproduction.

Better images for a non-technical audience come from professional photographers who fly small planes, zooming in at oblique angles and varying altitudes, using 35mm cameras and different lenses. The format is versatile and more expressive. Developers and architects have often commissioned some costly, low-altitude aerial pictures to show existing conditions before presenting a project. Planners have also used these images, especially in Europe, but usually filed them in the office.(7) Color aerial photographs in books or planning reports remain expensive to reproduce and distribute.

At this moment, aerial photography is becoming much more affordable and accessible because of the way that computers can interact with digitized aerial images. It is still expensive for a pilot to fly with a hand-held camera, and it is still true that audiences enjoy having an expert present to discuss aerial images. However, the cost of creating websites is decreasing, as well as the time that is required to download and view their contents. Aerial photographs can now be studied by the citizenry at large, since a small town library, an educational institution, a citizen organization, or a planning office can host a website with dozens of aerial color photographs. The potential to contrast aerial images of a town with aerial images of other towns allows for many lessons in land use (bad practice, good practice, better practice, best practice). Aerial images can also be tied to GIS parcel maps containing data about topics ranging from vacant lands to historic structures or environmental conditions, as well as to traditional planning documents such as zoning maps and written plans. Aerials can also be paired with a broad range of older maps, images, and documents for public history.(8) Citizens can access them for hours at home or in small groups, as well as with planners or historians in larger public settings. This flexibility allows citizens time to absorb and discuss complex spatial information and to integrate local knowledge with new images in order to evaluate development proposals.

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