Latest Contributions by MelitaKennedy

‎11-05-2020

Hi Xander, Yes! And they need converted to XYZ. There is an abridged Molodensky method that uses decimal degrees directly--but accuracy is a little less. After converted through the conformal 3D equation, the output XYZ need to be converted back to lat-lnng-ellipsoid h. That conversion is usually iterative but I think there are some direct but less accurate conversions. Melita

‎11-05-2020

Duh! mkennedy at esri dot com

‎11-05-2020

Hi Lauren, I'm very sorry for the late response. Can you post the equation/steps the surveyor gave you for the data? For CAD data it's sometimes possible to assign translation/rotation/scale values to a CAD layer. It's also sometimes possible to modify the projection parameters (scale factor, false easting, false northing) and create a custom coordinate system that gets the data to match up. I have two documents that discuss some of this. If you (or anyone else) sends me an email, I'll send them. They're pretty old now and written for ArcGIS Desktop so workflows may be different if you're using ArcGIS Pro. Melita

‎11-05-2020

Are you converting the input coordinates to radians and converting to XYZ? The main equations look okay to me.

‎11-05-2020

We don't support 3D Cartesian in ArcGIS yet. It is in the Esri projection engine, but not exposed in the software using the library. I'm sorry! Melita

‎11-05-2020

I don't think it's actually MGRS. MGRS is an alphanumeric system for locations. By default, it's only accurate to the nearest meter (+/-0.5, actually a little more) although we support MGRS strings up to mm precision. It might be UTM, which MGRS is based on.

‎07-20-2020

Hi everybody, I'm sorry that I didn't respond to this before. Both ArcMap and ArcGIS Pro support on-the-fly reprojection which often includes a geographic/datum transformation component. Both software packages use the same underlaying code, so if you have different results, it's usually because they're not using the same transformation. Open the map or data frame properties and make sure the same geographic transformation is being used. ArcGIS Pro will often automatically select a transformation, but ArcMap doesn't do that, so it's easy to have the two giving different results. Melita

‎07-20-2020

Hi Erik, I'm sorry for the delay in responding. There has been no update in the release of files/test data from NGS. However, NGS has said that they are going to delay the adoption of NSRS / 2022 for a few years. See Delayed Release of Modernized NSRS | New Datums | National Geodetic Survey and Track Our Progress - New Datums - National Geodetic Survey . The summary is that the official adoption will likely occur in 2025, although they'll keep the 2022 name. Meanwhile, we implemented for ArcGIS 10.8.1 and ArcGIS Pro 2 a variant of Lambert conformal conic projection that will be used by NGS for the new state plane and other zones. It was already supported but awkward to use. We're still following NGS closely. Melita

‎05-06-2020

Thanks, Justin. I just wanted to be sure! I have the files, but am swamped right now. I'll get to them soon. Melita

‎05-06-2020

Hi Robert! I don't see the attachment--maybe post a link? Is it the table of different map projections and their properties or the pdf file that lists projected coordinate systems, areas of use, etc? If it's the pdf file, look in the geographic coordinate systems pdf. That contains the vcs info too. Melita

‎04-24-2020

Hi Justin, Can you contact me via email so I can get some sample files, if possible. mkennedy at esri dot com The gtf file aren't supposed to be directly editable. The bit of binary at the beginning of the file contains version and string length so it's possible that it's getting messed up and we're failing to read it. Thanks, Melita

‎03-11-2020

Hello, What tectonic plate or plates is the data on? Are there other forces that would change coordinates like post-glacial rebound, seismic activity, subsidence, etc.? An area of interest in Australia versus New Mexico versus Washington would likely have different answers. Melita

‎03-06-2020

I'm sorry for the delay in answering. You can copy the string to a text file (use Notepad). Make sure that it's one line. Save the file with a .prj extension. Now you can import it in ArcGIS Pro through the coordinate systems dialog/picker.

‎03-06-2020

Hi Dave, Is there any chance I can get the DEM for testing? I haven't heard of your issue. If it's possible, and the file's not too large, you can send it to mkennedy at esri dot com. Melita

‎02-25-2020

Hello Stefano, We don't publish the EPSG dataset version with the Esri release. We do keep a list internally. Because we don't fully implement the EPSG dataset, there's usually a subset of objects that have been implemented at any EPSG dataset release. Note: Between 10.6.1 and 10.7.1, we did add more entries but I was selectively picking what to add so we didn't update the EPSG version number. ArcGIS build # EPSG Freeze date (not software release date) 10.4.0 5524 8.7.2 12/23/15 10.4.1 5635 8.8 02/15/16 10.5.0 6489 8.9.4 10/28/16 10.5.1 7333 9.0 06/07/17 10.6.0 8321 9.1.2 12/18/17 10.6.1 9270 9.1.2 12/18/17 10.7.0 10450 9.1.2 02/19/19 10.7.1 11595 9.1.2 05/31/19 10.8.0 12790 9.8.2 11/26/19

My Ideas

Latest Contributions by MelitaKennedy

Re: How can I get x,y in dec degrees from a poly feat serv using arcade?

Re: How do I get my CAD data to project correctly without georeferencing?

Re: How do I get my CAD data to project correctly without georeferencing?

Re: How can I get x,y in dec degrees from a poly feat serv using arcade?

Re: ArcGIS Pro: 3D cartesian coordinate system

Re: How to define projection of an .las file with an "unknown projection" that I know is actually in MGRS?

Re: On the fly projection is way off

Re: I heard the other day that there is going to be a big change in the coordinate systems that we are going to have to get used to in 2 years. Does anyone know about this?

Re: ArcGIS Custom Transformation (.gtf) shift inverted in v10.7

Re: Vertical coordinate system poster question ?

Re: ArcGIS Custom Transformation (.gtf) shift inverted in v10.7

Re: Area calculation consistency over time for thematic maps

Re: ETRS 1989 UTM Zone 32N 8Stellen

Re: How to “clear” the coordinate system of the “Map” to get it to “unknown” in ArcGIS Pro,

Re: EPSG release and ArcGIS Projection Engine

Re: The vertical transformations WGS_1984_To_EGM96

Re: The vertical transformations WGS_1984_To_EGM96

Re: NAD83 to NAD83 2011 transformation methods

Re: Formula For State Plane to Lat/Lon Conversion

Re: What is the projection for Russia and Alaska a...

Coordinate Reference Systems

Alaska GIS Users