Hello, is there a "good way" to determine if the planar or geodesic method should be used (for area calculation), when working with UTM ?
e.g: I am working with WGS 1984 UTM (Zone Nord) data and when calculating polygons areas, in square meter, I have the below results
# At buildings level (~1:2,000) the geodesic method produce a slightly larger area (1 feature)
# City level (~1:12:000) the planar method produce slightly larger areas (multiple features)
which applies to area, so it will be the projection you are using, plus your location and the size of the feature you are measuring that will account for the differences between planar and geodesic. See the tip at the bottom of the link
Field calculator expression is also a check