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Google's View of D.C. Melds New and Sharp, Old and Fuzzy

To obtain permission to fly over the District and take photos, the Geological Survey promised the Secret Service that as soon as the plane landed, images that could "jeopardize national security" would be deleted or edited, Geological Survey spokesman Doug Spencer said.

"When you think about it from a military perspective or a terrorist perspective," he said, "you don't want to put that information out there."

Soon after the Sept. 11, 2001, terrorist attacks, the agency took aerial photos of 133 urban areas across the country; it repeated the process in 2005 for many of the cities. Each city could determine which sites needed protection and, therefore, less clarity on the map -- some picked water treatment plants, military bases, power plants or government buildings, but there was no consistency.

"It was really at their discretion," Spencer said.

In June, Google Maps http://( and Google Earth http://( updated their satellite images of Washington and several other cities using the 2005 Geological Survey images, and Schiller began to explore. He selected the District, changed the setting to satellite, zoomed in as tightly as he could and began touring the city.

He soon realized that some parts were much clearer than others. He checked the source of the images, noted on the bottom of the map window, and concluded that the District was made up of images from different sources and years.

Google receives its photos from government agencies and commercial imaging companies. Imagery managers decide which sources offer the best resolution and most up-to-date information. For the map of Washington, Google opted for the highest-quality photos available rather than the newest information.

Schiller said he thinks Google should just use the 2002 map for the small spots the government has censored rather than the whole downtown area.

And he said he's puzzled that any level of blurriness is needed by anyone -- even the government -- especially because he recently took a detailed tour of a nuclear reactor south of Detroit via Google Earth.

"Where is the concept of national security in this?" he asked.

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