I posted the following in the Raster Design group, but I am not confident that too many people in that group will know what I'm talking about so I'll post it here as well:
I have GIS data imported from an ArcSDE database that are the base to rubbersheet scans of legacy maps for georeferencing. The native coordinate system for the database is HARN/CA.CA/Teale which appears in my MAP 3D coordinate systems and seems to be a well known system. For simplicity's sake, I would prefer to operate in the native coordinate system of our GIS database. After I get the map image georeferenced I try to use the EXPORT IMAGE routine from the Raster Design menu to save the image for future use, but there's no entry for HARN/CA.CA/Teale in the PROJECTED selection for the GEOTIFF export option. I have been able to export it from the GEOGRAPHIC 2D selection as LL83 coordinates, but when I try to reference that image in a drawing having a different coordinate system (CA-III for instance) no transformation is performed.
Does Raster Design truly understand and translate from one coordinate system to another? I have a suspicion the Raster Design doesn't reference the same coordinate system library the Map 3D does. Is there some secret location where I need to copy the coordinate system file? I've had no problem referencing DWG files from different coordinate systems in MAP 3D.
Thanks in advance for any help you can give me.
J Edward Leavitt
Ain't no RD, so I use opensource Gis to perform full Geotiff transformations: give a try to Qgis and Mapwindow, sir.
Thanks for the suggestion.
I'll check out those packages, but I'm developing a procedure that I'll need to teach to technicians who currently use Raster Design. Security protocols make it extremely difficult to get authorization to install any software not tested and approved by the IT people. The procedure needs to operate entirely within the Autocad environment so that I can automate it as much as possible because the technicians only have a vague idea about coordinate systems and projections.
Thanks again.
J Edward Leavitt
Raster Design does not reproject on the fly, it has the tools to rubbersheet and all but not reproject. Using Map3d and data connect (FDO) with the raster provider does reproject on the fly.
@ Murph
Sounds like mr.Leavitt's talking about the creation of a reprojected FULL Geotiff, not only a simple pair TIF+TFW...
In 2013 Map DOES try to reproject on the fly using MAPIINSERT. It's a new, undocumented feature that is broken as it doesn't read every GeoTIFF's file header correctly. This "feature" been confirmed to me through a support request.
Thanks for your responses.
I think engrtech nailed the problem. It doesn't seem like Map is doing any sort of transformation when reading a GeoTIFF into a projected drawing. After rubbersheeting an image Raster Design provides an image export routine that will save the image to a selected projection or datum. The export appears to work correctly since I can import that image into ArcMap 9.3 at the correct location. The choices of projections in RD is very limited and I can't find documentation to add to its coordinate system library, otherwise the export routine would be ideal.
Reading the GeoTIFF back into Map fails unless the coordinate system in Map is the same as for image file. This points directly at Autodesk's image import routine and its lack of a coordinate transformation, but what the hell do I know...I'm just a poor dumb surveyor.
Thanks,
J Edward Leavitt
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