I have succesfully overlaid several .dgn files created in one coordinate system onto GIS data of another coordinate system. I did this by copying and pasting a prj file in the coordinate system of the .dgn files, putting it in the same directory as the .dgn file, and naming it the same name as the .dgn file.
In most cases, this has worked well, but in some cases, it doesn't. I've remedied most of these cases by compressing the .dgn file.
I have one case where compressing the dgn file didn't get the data in it to overlay onto the data already in ArcGIS. I looked in the .dgn file and there are no reference files in it. Does anyone have any ideas concering why this particualr dgn doesn't want to overlay onto my existing geo data that is in a different projection/coordinate system?
Mark Janecek Urban and Regional Planner Wisconsin Dept. Transportation
Hello Mark, Is the particular DGN you are working with able to be overlayed in Microstation with other DGNS? If not, it may be that whoever created the DGN did not use the correct units and maybe didn't use actual coordinates for the design. It could also be that the DGN is in a different projection than what you are using for the others. If you can find out this projection, you can use ArcCatalog to define the coordinate system of the DGN and then when you bring it in to ArcMap you can perform a transformation to get it to line up. You have probably already tried all of this, but something to look in to if not. Take care!