G_AERIAL_MAP coordinate system/projection?

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G_AERIAL_MAP coordinate system/projection? Max Ogden 6/16/10 9:55 AM
Hello,

I am working with the G_AERIAL_MAP tiles but they seem to be projected
in a different coordinate system than the streets, satellite and
terrain layers. The latter 3 layers all use google's projection, EPSG:
900913 (GOOGLE), but the aerial tiles seem to be using a slightly
different projection.

I was wondering if anyone knows how the aerial tiles are projected?

Thanks,

Max Ogden
Re: G_AERIAL_MAP coordinate system/projection? Nianwei 6/17/10 10:55 AM
There is no EPSG code for that. It is not a typical coordinate system
in the sense that the X and Y directions are growing at different
rate. You can get a basic sense by imaging a camera tilted at 45
degree angle then retreat to infinite distance, but you project the
ground subjects to the tilted image surface.

One axis is at square root of 2 scale of the other. See
http://code.google.com/apis/maps/documentation/javascript/v2/reference.html#GObliqueMercator

It's not a trivial task to do custom work on Obliques.