Hello, For some reasons there are two versions of Finnish KKJ parameters hanging around in the projection libraries. I checked that the situation is the same at least in MS4W and FW Tools Windows packages. In the files "\FWTools1.2.2\proj_lib\epsg" and "\ms4w\proj\nad\epsg" the definition are like this: <2393> +proj=tmerc +lat_0=0 +lon_0=27 +k=1.000000 +x_0=3500000 +y_0=0 +ellps=intl +units=m +no_defs <>
In the same directories the corresponding "esri" files include also the towgs84 parameters: <2393> +proj=tmerc +lat_0=0 +lon_0=27 +k=1.000000 +x_0=3500000 +y_0=0 +ellps=intl +towgs84=-90.7,-106.1,-119.2,4.09,0.218,-1.05,1.37 +units=m +no_defs no_defs <> In practice this means that if you re-project something to/from anything else than between the KKJ zones a) Projections given as epsg:2393 and esri:2393 (or taken from esri .prj file) will lead to different result. b) If epsg-reference is used the result is always wrong resulting to something like 100-150 metre position error. I think that the definitions in epsg file should be corrected. Or is there some reason, historical or other, for not including the towgs84 parameters there? Regards, -Jukka Rahkonen-
