I have a question that's come up at work and I can't find a definitive answer.
If I'm going to create an ArcServer REST service, what is the ideal projection? I know a service has the option of re-projection data but this should have a server side performance hit on each callback. I'm working with stream/river data and it may have high demand for a while..
I know ArcGIS on-line uses 3857 Web Mercator and so do most base maps. However many of the data REST Services I use require WGS-84 with Decimal Degrees. (GeoJSON for example)
I'm in NY and it appears many services are in UTM zone 18, but Buffalo isn't even in zone 18, so this isn't ideal if I have it return Meter coordinates.
I'm looking for the best solution, that would return the data in my web map (wgs-84) the fastest with the least demand on the server.
It's a dynamic map service that is constantly updated so caching the service is not feasible.
Your thoughts?