Need help regarding suitable projection for base map and dynamic map

[SunilPalkar]

Hello All,

Good Morning,

I have lot of geographic data in shape file format and  we are going to host few data on server 10.1 [and then will publish in Java script API (v 3.0) ] . I recently gone following article regarding projections http://blogs.esri.com/esri/arcgis/2009/11/20/arcgis-online-moving-to-google-bing-tiling-scheme-what-... it states that you need to convert your projection to WGS 1984 Web Mercator.

I have already shape files in WGS 84 (degree) format & My question is that Do I need to convert all these shape files to WGS 1984 Web Mercator format ?? ( Because I want to use this data for ArcGIS Server(10.1)  and then in JSAPI  for custom applications)

Any help/suitable methodology is highly appreciated..

Thanks in advance : )

[JohnGravois · Accepted solution]

hi steve,

you can certainly publish your shapefile data in WGS84.  the reason it is often suggested to reproject to web mercator is so that you can mash things up with google/esri//bing/osm without asking your own dynamic map and feature layers to reproject on the fly.  depending on the data you are trying to display, this can give a noticeable performance improvement.

the blog you linked warns specifically about caching services in a projection other than web mercator.  this is because it is NOT possible to overlay two different tiled map services that use different coordinate systems.

[SunilPalkar]

Dear John,

Thanks for your reply.. I like your post and justification ..

You are simply great !!!

Thanks  : )

hi steve,

you can certainly publish your shapefile data in WGS84.  the reason it is often suggested to reproject to web mercator is so that you can mash things up with google/esri//bing/osm without asking your own dynamic map and feature layers to reproject on the fly.  depending on the data you are trying to display, this can give a noticeable performance improvement.

the blog you linked warns specifically about caching services in a projection other than web mercator.  this is because it is NOT possible to overlay two different tiled map services that use different coordinate systems.