The GEO-Jobe Blog

This year begins a new flying program for the much heralded and first-in-the-nation Basemap program in TN (TNBMP). As I write this, TDOT is capturing western TN counties on a county-by-county regional (~25% of the state per year) coverage area at 1″=200′ scale county-wide. Next year (’09) we’ll see many middle TN Counties receiving the imagery.

Did you know that the deliverable, a 1″=200′ scale product, is going to be a lower resolution than you are used to in urban/suburban areas (your 1″=100′ scale tile areas). The original TNBMP specs called for counties to receive 6″ pixel resolution imagery in urban areas and 2′ pixel resolution in the rural areas. The new program splits the difference by providing 1′ pixel resolution county wide. Though it will be in color, it will not have the detail and clarity where you really need it. This is one of the trade-offs for getting free imagery from the state at the local level. One image resolution is cost effective and covers the widest area. However, it won’t meet the needs of all local users.

In the picture above, the top half is a 6″ pixel product and the bottom half is a 1′ pixel product. This is a representative sample of what the relative differences will be from what you are used to and what you will be getting for those urban/suburban areas. For many of you this will be OK. Others may find it difficult to perform some traditional tasks that require the quality of the higher resolution images.

As a provider of photogrammetry services, GEO-Jobe can provide custom pricing for your higher resolution image area that follows your 100 scale tiling or even your urban growth boundaries. These would be delivered in accordance with the TNBMP standard with TIF and Generation 2 and/or 3 MrSID deliverables. We also provide ancillary products like updated contours and planimetrics based on the TNBMP standards. And of course we use local TN partners so you’ll keep it “Made In Tennessee”. Got questions? Call us at 615-883-0085.

Filed under: Data, Maps, TNBMP