How does Microsoft get those 3D models for Virtual Earth that make its Live Maps service so darn good? The answer is simple: if you want something done right, you have to do it yourself.

It turns out that Microsoft manufacturers its own UltraCam to get the job done. Although the 3D models created for Virtual Earth come from more than just one source, the majority of the data comes from the large format digital aerial UltraCamX (UCX). Mark Brown, Senior Product Manager for Virtual Earth, describes the device by saying:

This thing is incredible, 216 mega-pixels with a panchromatic image size of 14,430 x 9,420 pixels, capturing data at over 3 GBits/sec, 13 CCD's - 7 pan and 4 color (RGB + Near IR) and 14 CPU's to process the raw images and data in real-time. The data units for the camera hold 1.7TB, enough for about 4,700 images. Since they are swappable the only limitation to how much imagery you can collect is how big your aircraft is to hold these units.

The image quality can be very high, thanks to a 1:3 pan-to-color ratio. The UCX collects pixels at a sustained rate of 3Gb per second, and the average image has a size of 380MB! Who wants to take a guess at the price tag for this baby?

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