scale bar With the move to web mercator we are moving into a global scale level world. The base map services that we offer fall in between the world view, scale 0, and the much more zoomed in manhole cover scale - 20. The table below describes the base map that we offer with it’s min and max zoom levels. The table below that describes the scale to which that zoom level is equivalent to.

Handling these different scales requires some extra effort within the esri javascript api version 3.x. In order to make these services accessible and easy to work with we have created the layer selector widget. You can read more about this widget and examples of it’s use in this blog post or you can browse to atlas.utah.gov to see it in action.

Base map Min Zoom Max Zoom
Color IR 0 18
Imagery 0 20
Lite 5 19
Overlay 5 19
Terrain 5 19
Topo 5 17
Zoom Scale
20 1128.497220
19 2256.994440
18 4513.988880
17 9027.977761
16 18055.955520
15 36111.911040
14 72223.822090
13 144447.644200
12 288895.288400
11 577790.576700
10 1155581.153000
9 2311162.307000
8 4622324.614000
7 9244649.227000
6 18489298.450000
5 36978596.910000
4 73957193.820000
3 147914387.600000
2 295828775.300000
1 591657550.500000
0 591657550.500000