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bmac2012
2017-12-15, 11:46 PM
Hi all,

I have a .tif and .tfw file for hi-res imagery from the USGS EarthExplorer and it's metadata shows UTM/NAD83 Zone 13 Meters. I'm trying to import the aerials into Civil3D 2016 using all the typical commands (mapwspace, etc) in order to have it shown correctly in a State Plane, Foot datum. Has anyone done this process before and can help?

Some things I've tried:
1. CAD file set to the coordinate system of the image, then new file set to feet and the coordinate system I want (Colorado State Plane Central, Foot) and MAPWSPACE and query the image into this foot file.
2. The same as 1, but with no datum/no projection set on everything.
3. Both 1 and 2 and inserting the image with MAPIINSERT into the first file with both "feet" and "meters" as the choices for different times.

Best I can do after a query is end up with an image that appears correct in terms of northing/easting location, but when I measure the image roadway width, they still show up as the correct widths, but as meters (so in my foot file, I measure 3.5' for a lane with, which should be 10.5 feet...the perfect conversion from feet to meters). The drawing is all set to read as feet, all units are feet, and the datum is Colorado State Plane feet.

I can also get the image to read in feet (in terms of measuring the road widths), but based on the northing and easting it looks way off in the wrong space.

Has anyone used these files before and had success???

I'm also wondering about how to get LIDAR data from EarthExplorer to come into the right space of a foot file as well.

Any help would be great. Thanks everyone!

Brandon

Jmurphy
2017-12-20, 12:13 AM
Make sure you have the Colorado State Plane Central, Foot coordinate system set in your dwg, then use data connect (FDO) and select Raster as the file type. Browse to the tif file and connect to it, in the dialog box make sure the coordinate system for the image are showing. Then just add to the map. Also make sure the tif and tfws file are in the same folder and not to far away from the C: drive directory. (Short file path)

bmac2012
2018-01-11, 07:18 PM
Thanks for the reply, Murph. I have yet to try this out (time/budget constraints, of course) but this seems like a different way than I've tried. Once the aerial is in the right spot and clearly measuring in feet, then I'll know if my import of LIDAR data is correct as well. I'll follow up here once I get a chance to try it.

bmac2012
2018-01-16, 04:26 PM
@Jmurphy

The FDO connect seemed to work well. Needed to override the aerial coordinate system, as it came up "Unknown" in the dialogue. The metadata from USGS says it's in UTM NAD83 Zone 13 Meter though, so easy enough to change. Thanks for your help Murph!

For anyone else reading this wanting to know if the Lidar works, it does. Just create a point cloud and choose your LAS file. Everything falls into place.