topic X Y Long and Lat projecting to the wrong location!!! in Geoprocessing Questions

X Y Long and Lat projecting to the wrong location!!!

StevenRiley — Sat, 30 Jul 2011 01:06:33 GMT

I'm new at this so forgive my newness : )

I am currently adding an excel table with Lat/Long coordinates. However, when it projected into the layer, it is not in the correct location. In this case Colorado. It shows up in Nebraska.

How do I get the coordinates to map over correctly?

My steps:

Add data.
Select the Excel sheet.
Now it is in my table of contents.
I right click the Excel sheet and select display XY data.
I change the fields to be correctly set for the X and Y.

Here is the info on the description:

Projected Coordinate System:
Name: USA_Contiguous_Albers_Equal_Area_Conic

Geographic Coordinate System:
Name: GCS_North_American_1983

I hit Enter.
Then Ok.
Now I have the sheet1event and sheet1 in the table of contents.
Sheet one has table data. Sheetevent has no data.
Sheet1event has the following info:
Data Type: XY Event Source
Location: C:\Documents and Settings\USA COMPUTER CITY\Desktop\Project 2\mercury_colorado_sites.xls
Table: Sheet1$
X Field: Latitude
Y Field: Longitude
Has Object-ID Field: No

Projected Coordinate System: USA_Contiguous_Albers_Equal_Area_Conic
Projection: Albers
False_Easting: 0.00000000
False_Northing: 0.00000000
Central_Meridian: -96.00000000
Standard_Parallel_1: 29.50000000
Standard_Parallel_2: 45.50000000
Latitude_Of_Origin: 37.50000000
Linear Unit: Meter

Geographic Coordinate System: GCS_North_American_1983
Datum: D_North_American_1983
Prime Meridian: Greenwich
Angular Unit: Degree

Again there is no data in fields on the sheet1event table.

When I do a Full extent I can see the sheet1event symbol but it is located in what would be Nebraska.

I ran the layers in define and then projection with Geo Transformation as directed for the exercise I was working on.

It seems that may be the issue although I'm not sure.

I also can't seem to set up the sheet1event to see any data in the fields such as long and lat but it is in the sheet1.

I also cannot do the Geo Trans. I was adding the NAD_1983_to_WGS_1984_1.

Thank you for any assistance in advance.

Rookie Steven 😃

Re: X Y Long and Lat projecting to the wrong location!!!

markdenil — Tue, 02 Aug 2011 18:06:45 GMT

You write that your event layer reports:
X Field: Latitude
Y Field: Longitude

That would give you some problems, I might suspect.
the x values would be in your Longitude field, would they not?
and the y values in Latitude?

Are these really latitide and Longitude values in your table? The longitudes should be between 102 and 110, and the latitudes between 37 and 42 (for Colorado).
You cannot plot lat/long values into an Albers Conic coordinate space and expect usable results.
Plot to a so-called geographic coordinate system, then project it.

If the table values are much larger numbers than noted above, maybe they are indeed Albers coordinates. Then the question becomes: what Albers parameters are correct (central meridian, standard parallels, possible false eastings or northings)

Maybe, too, you have degree, Minute, Second values in you table? or Degree and decimal minute?

There are lots of variables just in getting your points created properly. It is not suprising later steps don't work if the first step is all wonky...

Re: X Y Long and Lat projecting to the wrong location!!!

StevenRiley — Tue, 02 Aug 2011 18:39:00 GMT

Thank you for providing the info mdenil. 😄 I like the word WONKY. I'll use that going forward. 😃

Onto the issue at hand... I will verify everything and fully appreciate the clarification. It helps me to understand the process much better.

I'm learning and this feedback is very welcomed.

Incorrect data in, and the wrong set of variables on the back end will show.

Okay back at it.