I use QGIS Lisboa and need the length of some shapefiles. When I use the field calculator the results are always around 30% higher than in real, also than a measuring in the map.
Does anybody have a similar problem or knows about a solution?
Geographic Information Systems Stack Exchange is a question and answer site for cartographers, geographers and GIS professionals. It only takes a minute to sign up.Sign up to join this community
Field calculator uses the CRS of the shapefile, while measurement tool uses the projects CRS, until you uncheck
The two CRS may be the same, or not.
You can right-click on the layer
-> Set Layer CRS for Project, unless you are using openlayers plugin for background layer.