Projection Issues

Question

I am working with NC shapefiles, I downloaded a national cities shapefile and I can't seem to line them up, actually you can't even see the layers in the same view. I have tried many times to re project in Arc Catalog, I even took the layers .prj file and copied and pasted it into the cities .prj file and it still did not work. I made the layer undefined and brought it into a projected data frame thinking it would project on the fly and that did not work. I projected it in WGS1984 thinking arc will know how to make it line up with NCs' state plane and that didn't work either. The only difference I have noticed comparing projection data is that the source extents are different. I can't see anyway to change them.
an example of the difference when I am in ArcMap and pull up it's source properties
the file where the projection is correct Left: 363485.468756 m the file where the projection is wrong Left:-178.877400 m

any help would be greatly appreciated!

Niki

What are the projections being used? I've had a problem similar to this before and it was because it was in the wrong UTM zone. 14 instead of 13 for example. — Pete, Jun 21 '13 at 15:25
sorry just saw this, I was in NAD 1983 North Carolina State Plane 3200 feet — Niki, Jun 21 '13 at 16:50

score 0 · Answer 1 · answered Jun 21 '13 at 16:13

There must be a duplicate of this somewhere!

You are changing the coordinate system information in ArcCatalog on the data layer's XY coordinate system tab of the property page. That updates the metadata only. The data's extent and coordinate values are unchanged. They're still in the old coordinate system. This is the same workflow as using the Define Projection tool in ArcToolbox rather than the Project and Project Raster tools.

The 'bad' data is in decimal degrees which is why the coordinate values are so small. Define it back to what it was (probably NAD 1983). ArcMap will then be able to project on-the-fly / in-memory to the data frame's coordinate system. If you want to permanently convert the data to the same coordinate system as the rest of your data, use the Project tool or once it's overlaying properly in ArcMap, right-click the layer in the table of contents and select Data, Export Data. In that dialog, use the data frame's coordinate system when you export the data.

thanks so much for the response, defining it was the issue! – Niki Jun 21 '13 at 16:51 — Niki, Jun 21 '13 at 16:51

Projection Issues

1 Answers1