[Qgis-user] strange results when calculating area and perimeter

[rob vech]

Hello,
I'm using the wounderful (:)) qgis Dufour 2.0.1 and I'm trying to 
calculate area and perimeter from a simple shapefile with CRS WGS84UTM32 
following these steps:
1) set up the CRS of the project to WGS84UTM32 (on the fly 
transformation is checked)
2) load the shapefile
3) click on it with the identifier tool (identify features) I obtain:
- area: 19.321 km²
- perimeter: 0.221 m (!!!!)
4) then I try to calculate in the table ...
- area: 2,301,030,218 while in the preview was 19,320,205.394043 (!!!!)
- perimeter: 2,859,402,286 while in the preview was 20,391.7709396732 (!!!!)

then I modify the general CRS settings for new project (settings --> 
options) to WGS84UTM32 and, after reloading qgis, I did steps 1, 2 again 
and I obtained:
3bis) in the identify tool:
- area: 19.321 km²
- perimeter: 20.392 km
4bis) and in table:
- area: 19,320,205.3
- perimeter: 20,391.771

The second way seems to give more consistent results.
But why should I setup the general CRS option if I've already setup the 
project CRS?
Shouldn't the geometry function all referred to the project settings?
There is something of wrong in my first procedure?
Thank you in advance
rob





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