I received a set of drawings that were drawn in millimetres but in the correct coordinate system; I use GDA94 with my coordinates in metres, so this should theoretically be a simple fix using my usual process:
- UNITS > change 'millimetres' to 'metres'.
- Select all > SCALE > base point 0,0 > .001 scale factor
Once this is done, checking the coordinates on the status bar on AutoCAD indicates that my data is in the correct scale and coordinate system, but once I bring it into ArcGIS, it projects nowhere near where it's meant to go and with coordinates that probably aren't even in the same coordinate system.
What is happening? I've used this method before and it usually works, I'm not sure what's happening in this case.
EDIT: the coordinate system I am using is a variation of GDA94 (Perth Coastal Grid 1994). A centre point in the CAD drawing shows a coordinate of 59501 E, 273281 N, which is correct for my purposes. However, zooming to the same layer overlayed in ArcGIS produce a central coordinate of approximately -845 E, -3346 N -- the data doesn't even display, but it could be due to CAD hatching not importing.