@KDAddison
J2000, MrSID, and geotiff formats all have their projection built into the header. Other formats such as jpeg, tif, and png must have a separate corresponding ‘WORLD file’ for proper image insertion.
You can’t change the original projection that’s in the header. The header was established by the image’s author when the image was originally created. You can make a copy and re-project the copied file but you cannot change the original projection.
If you are running Map3D, you’re better off running something other than IINSERT. That’s a Raster Design command, not a geospatial Map3D command. FYI, M3D has more appropriate commands to handle geospatial formats such as J2000.
First, you’ll need to assign an appropriate coordinate system. Your drawing units will adopt or inherit the units of that assigned CS and that means you'll be using either Feet or Meters, not inches. Never ever. There are no ' known coordinate systems' that use inches.
If you don’t assign a CS your image won’t know where to plop down in modelspace and this means the image won’t be consistent with Bing imagery. Same with other geospatial linework you downloaded or acquire from others, they won't be geospatially accurate if there's no assigned CS.
If you’re an advanced and experienced Map3D user, connect to your J2000 using the Data Connect Palette. Be sure you know the native CS given to the J2000 by its original author…..if M3D reads the image’s projection incorrectly you can manually correct it by overriding it. As long as the image has a valid projection Map3D will perform any needed transformation from the native CS (or your overriding CS) to your assigned CS.
Or you can use Map3D's MAPIINSERT command. This procedure will also convert the image’s native units to the units used in your assigned CS (such as meters to feet).
If your drawing is using inches instead of feet then you’ll need to convert the drawing from inches to feet beforehand. You can’t convert a coordinate system to inches.
If your drawing is using inches, your X/Y units (eastings, northings) would NOT be consistent with any projection, meaning all objects would be in the wrong spot because their coordinates wouldn't be in feet. Your workflow should be (1) convert to feet then (2) assign an appropriate CS (MAPCSASSIGN) like a CS that uses feet, such as State Plane with the appropriate Zone. There are no coordinate systems that use inches.
If you don’t assign a CS at all, then your drawing would NOT be geospatial and you might as well use the non-geospatial ATTACH command to insert it which is the same command used by those who only draw using plain vanilla AutoCAD.
Chicagolooper
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