[Qgis-developer] coordinate capture plugin with QGIS dataset

[Otto Dassau]

Hi, 

I wanted to create an example for the coordinate capture plugin and had a
problem with the alaska dataset [1]. The data are projected in Albers Equal Area
with unit meters (EPSG 2964).

PROJCS["NAD_1927_Albers",
    GEOGCS["GCS_North_American_1927",
	DATUM ["D_North_American_1927",
	     SPHEROID["Clarke_1866", 6378206.4,294.9786982]],
	     PRIMEM["Greenwich",0.0],
	     UNIT["Degree", 0.0174532925199433]],
    PROJECTION["Albers"],
    PARAMETER["False_Easting", 0.0],
    PARAMETER["False_Northing",0.0],
    PARAMETER["Central_Meridian",-154.0],
    PARAMETER["Standard_Parallel_1", 55.0],
    PARAMETER["Standard_Parallel_2",65.0],
    PARAMETER ["Latitude_Of_Origin",50.0],
    UNIT["Meter",1.0]]

As far as I understand the procedure inside the plugin is:

- define the correct projection for the alaska data (EPSG 2964) in the project
properties dialog and activate OTF
- load an alaska dataset layer
- start the plugin and define another projection in the first row (click to
select the CRS...) e.g. WGS84 (EPSG 4326)
- click on the coordinate capture icon and click somewhere on the canvas to grep
some coordinates

=> first row should show the lat/lon WGS84 values and the second row EPSG 2964
coordinates for the alaska dataset. This does usually work fine for other
projections but not for the alaska dataset. I found this problem in the QGIS
forum as well but it doesn't seem to be solved:
http://forum.qgis.org/viewtopic.php?f=2&t=1384

There is probabaly something wrong with the projection definition of EPSG 2964.
A new parameter as far as I remember is +to_meter=0.3048006096012192, before it
was simply +units=m.

any help from projection experts is welcome :-)...

thanks,
 Otto

[1] http://download.osgeo.org/qgis/data/qgis_sample_data.zip