I’m new to QGIS and georeferencing raster data. I have a raster dataset with unknown CRS. The coordinates for goerefencing the raster data with reference points (x = 589 Y = 1483
/ x = 500 Y = 1500
) from an archaeological digging raster. The digging site is in Switzerland. I should georefernce that raster data, how do I have to set the proper CRS? I tried several time but failed and I have no clue how to proceed.
1 Answer
Archaeological digs usually use a localized grid, that while it may be originally based off a national grid, is customized to fit the local demands. these grids might be orientated to fit the archaeological architecture, topography, and sometimes to force only positive values of east/north in order to make measurements easier.
Georeferencing this raster should probably be done based on a high resolution aerial image of the dig site. the 0/0 location of the grid might be a prominent landmark surveyors used to plan out the grid.
the CRS itself can be a default custom meter grid, with the datum either WGS84 or ETRS89. The relatively small scale of the site means you don't have to worry much about deformities.