# Extracting lat/long from positions within scenery tiles

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Hi Art.Each photoreal tile represents an actual LOD13 area in the FS world.The tiles are 256 x 256 ( or 2^8 ). We know the LOD13 span for longitude ( 120 / 8192 or 0.0146484375 degrees ), and latitude ( 90 / 8192 or 0.010986328125 degrees ). 8192 happens to be 2^13... which is why it is called LOD13.2^21 ( 2097152 ) should be the span of pixels in a photoreal tile:longitude = ( 120 / 2097152 ) = 0.000057220458984375 degreeslatitude = ( 90 / 2097152 ) = 0.00004291534423828125 degreesIn other words, ( 0.0146484375 / 256 ) is the span for longitude for the pixels, and ( 0.010986328125 / 256 )is for the latitude span of the pixels.If you know the NW corner of any tile, then you should be able to calculate the exact position of each pixel within each tile using the above spans. Position 1,5 from the NW corner would be:( W + ( 1 * 0.000057220458984375 ))( N + ( 5 * 0.00004291534423828125 ))Each pixel, of each photoreal tile, has an exact address in the sim. The actual math is actually pretty simple.Dick

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Just what I needed to know. Thanks.Art

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