The base map services are ArcIMS image services primarily intended for on-screen display of data in ArcMap and for use in internet applications. To manipulate the cartographic characteristics of the data or perform analytical functions download the required data sets to your local server from the Resource Data Gateway.
These services are generally intended to be used in combination, as demonstrated in the sample mxd files. The display threshold of many layers may prove to be difficult to use in isolation
When using a projected data service, such as Digital Raster Graphics, the current projection system of the data frame should be set to match the UTM zone of the service. When loading a new zone it helps to clear the current projection of the data frame.
Vector services will project on the fly to match the current projection system of the data frame. While this is possible to do with raster data sets it is not as efficient.
Scale thresholds are set for each layer, zooming in or out may change the set layers available for viewing. When viewing a raster data set, such as Digital Raster Graphics, the category of DRG being displayed will change to avoid pixeling the image.
The entire service can be turned off and on by checking the layer in the table of contents. Layers within each service can be turned off and on by expanding the content listing for the service and checking the layer in the table of contents.