Anyone know how to insert the geotiff's into cad at the correct location.?ÿ I am using C3d 2019
I can download the tiffs from Topoview https://ngmdb.usgs.gov/topoview/viewer/#4/40.00/-100.00 ?ÿ but i am unable to get them to insert in the correct location.?ÿ
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When downloading, what are you selecting for your coordinate system and other attributes?
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I'm guessing you're not aligned with the assignment of the coordinate values in your C3D template/drawing.
How far are you off?
It just downloads as a Zip file and extract it.?ÿ?ÿ
I can get the tiffs to align with Geoviewer and Arcgis just not with cad.?ÿ
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Are you using raster? Its an add on for C3D.
Yeah Arcmap is fully functional out of the box with that, C3D not so much.
Try MAPIINSERT
I type GEOTIFF at the command line.
MAPIINSERT (sic). You will need the .tfw file that accompanies the .tif, both together in the same subdirectory. Also - the file name and path will need to be less than 156? characters.
MAPIINSERT has had problems reading the world file since forever. I have had decent luck with the IINSERT command (which is different), but that is still hit and miss.
Setting your coordinate system and units can make it work, but not always.
In many cases I simply give up, open the world file with notepad, find the pixel size and insert location (which is top left, not bottom left, of image), and manually place it in CAD.
There are six lines in the world file. First is pixel width in X dimension, next two lines are rotation about x and y axis, next line is pixel height in Y dimension (should be same as the first line but with a negative sign), and last two lines are X and Y coordinates (respectively) for the top left corner of the image.
It's also worth noting that many of the older geotiffs are actually referenced to NAD27. Open the PRJ file to see what projection is being used...
no luck with any of the commands, This is how it comes into Arcmap.
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I can't be of much help. Sometimes GEOTIFFs come in correctly, sometimes not. Sometimes a TIFF file comes in according to the origin and scale file, sometimes not. Sometimes I can manually position a PNG file according to the accompanying file, sometimes not.
That's screwy - it looks like a UTM projection (scale factor 0.9996, latitude of origin at equator, false easting of 500000), but the central meridian should be a multiple of three for UTM, since the extent of a UTM projection is six degrees of longitude.
Wonder if these things are custom projections centered on the longitude of the map extent?
Have you tried LizardTech?
Try to export the file and check 'write world file'; then you can use the world file to import as a regular tiff or manually fix after import.
It works fine in lizardtechs- geoviewer, ?ÿI got a new computer and my graphic card doesn??t like geoviewer. ?ÿCan??t zoom, I contacted lizardtech and it??s a know issue with no fix. ?ÿ
Try QGIS (free GIS)
I am not sure how to strip out the 4th band in QGIS. I do know how to get the TFW in both.
QGIS works perfectly to export the tiff to whatever coordinate system you need.?ÿ Fly's right into CAD.?ÿ?ÿ