Silverlight Map with ESRI Imagery

Question

I have a map service which is using data from a local repository, viewed using the ESRI Silverlight API. I am dynamically adding a tiled map service for imagery from ESRI.

The map service can be viewed here: http://server.arcgisonline.com/ArcGIS/rest/services/ESRI_Imagery_World_2D/MapServer

When the tiled map service is added, I can not zoom in closer than 0.002 Decimal Degrees, regardless of whether the map service is visible or not. This is despite the fact that according to the ArcGIS Services Directory, the imagery layer has levels of detail at much smaller resolutions.

Is there a reason why I would not be able to zoom in closer than 0.002 Decimal Degrees?

Answer 1

Use the MinimumResolution property on the Map control. This will allow you to zoom in to a smaller extent.

On a side note, it is recommended that you use the newer Web Mercator services rather than the old 4326 services. For imagery, the Web Mercator endpoint would be http://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer. See this ArcGIS Server blog post for further information. Note in particular where it states "the old services will remain available for a minimum of six months. They will be offered “as is” and will not receive any further data or cartography updates." We are well beyond that six month window, so aside from the 4326 services having stale data, they may be taken offline.

Answer 2

Generally the tiled services prevent you from zooming in past the lowest level of the tiled services cache. If you have your own service which is dynamic and you add to the application then you will be able to zoom past as the other service will visualise.

Hope this helps, CDB