Geotiff coordinate conversion

[Anonymous]

My state has a GIS available on the web that I can export a GeoTIFF or JPG with Georeferenced data. I'm wondering if anyone can help me troubleshoot why I've been unable to get the GeoTIFF to import into CAD in the correct coordinate system. I reached out to the State and they tell me the GeoTIFF is in Web Mercator Auxillary Sphere coordinates. My drawings are in NAD83 State Plane Feet.

I've using mapiinsert my drawing and also creating a new drawings with the Mercator coordinates and then XREFing into my drawing in the NAD83 coordinates but both ways the image is in the wrong quadrant and not anywhere close to the right location.

Thanks for any suggestions you may have.

[Pointdump]

Hi Michael,
Welcome to the Autodesk Forums.
MAPIINSERT can't transform, so if your GeoTiff is in Web Mercator Coordinate System, then your drawing must be assigned same for it to be placed correctly.
Raster Tools IINSERT will transform, so if you have Raster Design you're golden.
If you transform and save the GeoTiff in 3rd party programs, like QGIS or Global Mapper, etc, then you can MAPIINSERT your GeoTiff in a drawing assigned a State Plane Coordinate System.

Another way would be to use a Map Attach/Query. I don't think there's any way to transform an XRef.
Dave

[jae.kwon]

Even the best transformation will typically be a few feet off.

I usually get best results surveying a couple of easily identifiable points and lining it up manually with ALIGN command.

[ChicagoLooper · Accepted solution]

You can try this:

1. Start with a brand new OOTB imperial template. Assign your State Plane coordinate system. On command line enter MAPCONNECT. On the left, select 'Add Raster Image.....' then click the Browse to image button. Next, browse to and select your image=>Click OPEN=>Click CONNECT. See Image-1.
2. Verify the NATIVE COORDINATE SYSTEM of the image appears in the column labeled 'Coordinate System.' Click the ADD TO MAP button to add your image to modelspace. See Image-2.
3. If image's coordinate system in not correct, you'll need to edit it to the correct one then click Add to Map button. DO NOT EDIT THE COORDINATE SYSTEM OF MODELSPACE. See Image-3.

Image-1

Image-2

Image-3

@Anonymous  wrote:

<< GeoTIFF is in Web Mercator Auxillary Sphere coordinates....>>

I believe the coordinate system your image is referenced against is named WGS84.PseudoMercator by AutoCad (EPSG 3857). The easiest way to assign this CoordSys to modelspace is to enter MAPCSASSIGN on command line then perform a search. See Image-4.

Image-4

[Anonymous]

I tried this workflow and nothing shows up in my modelspace. All my layers are on and thawed and no .tif files get added to the external references plan. Interestingly, DATA CONNECT does not automatically pick up a coordinate system in the .tif file so there may be something wrong with the states .tiff header which is not allowing C3D to autodetect the coordinate, I had to manually Edit Coordinate System and set it to PseudoMercator. Once it looks like the attached screenshot I click Add to Map and nothing happens and nothing is added to the map.

I looked around my computer for Raster Manager but I can't find anything so I'm thinking I might not have Raster Manager. Would it show up in my Start Menu if I had it installed? How do I launch it/figure out if I have it? I tried both MAPIINSERT and IINSERT but no joy, it's way off, about 33,000,000 feet away and in the wrong quadrant.

[Anonymous]

Also I couldn't find a "OOTB imperial template" we have our company template and an acad.dwt on our server but both of these already have the State Plane coordinate system. I looked around on my C drive but I couldn't find any template files in there.

[Pointdump]

Michael,
Can you post your GeoTiff? Or maybe a link to where you got it?
Dave

[Anonymous]

The .tif file is attached.

The website is https://anrmaps.vermont.gov/websites/anra5/. Then you can search the address 515 sherman road, waitsfield, vt and chose the Tools->Export button to export a geotiff

[Pointdump]

Michael,
Thanks for posting your Tiff.
If you had Raster Design installed there would be a "Raster Tools" Tab, so you probably don't have it.
Several different ways to get that Tiff into your drawing. Here's one way:
Start a new drawing assigned WGS84.PseudoMercator Coordinate System. MAPIINSERT your Tiff. Save and Close drawing.
In your VT83F drawing, >>>Attach and Query<<< the WGS84.PseudoMercator drawing. Bam! Done!

Dave

[ChicagoLooper]

Only 1 step.

I was able to skip the QUERY and do this in only one step. 

You may do as Mr @Pointdump  has sugessted in post #9 of this thread, but you can also use a more streamlined and direct approach. This involves using the DATA CONNECT Palette, AKA an FDO connection (Feature Data Object).

A data connection is a built-in function that TRANSFORMS your image's native coordinate system, WGS84.PseudoMercator, to your modelspace's coordinate system which is VT83F. The image above shows the results of using a Data Connecton. Bing Hybrid has been turned ON and serves to verify the TRANSFORMATION from one coordinate system to another......and all this occurs without using a QUERY. 

[ChicagoLooper]

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@Anonymous wrote:

<<Once it looks like the attached screenshot I click Add to Map and nothing happens and nothing is added to the map.>>

---

Thanks for uploading the image of your Data Connect palette.

What happens if you use the Data Connect Palette on a clean, brand new template and not an existing drawing?

Once you have clicked 'Add to Map' did you Zoom Extents?

[Anonymous]

This solution did end up working for me. I was able to use MAPCONNECT on a file is State Plane, connect the raster file, I have to manually edit the coordinate system to Pseudo Mercator and then click "Add to Map". Interesting nothing's added to my map until I run the command MAPWSPACE and as soon as I run this command the image is added in the correct positions. Any ideas why this would be? Thanks for your help!!

[sfashah]

hi everyone , i have tiff image with coordinates and i want to convert in jpg because tiff image size is too large 3.3GB so if possible to convert from through to any software and plugin?