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Exactly - Arc is transforming these points ‘on the fly’ as it is described, as one data frame can only show one projection at a time. That is to say, you can only ‘look’ at your data through one projection at a time. So that transformation puts them in the same spot as the various characteristics of the NAD83 revisions are well known. Best, Forrest On Wed, Oct 10, 2018 at 11:54 AM Jonathan Hall <[log in to unmask]> wrote: > I agree with Keith > > On Wed, Oct 10, 2018, 10:46 AM Miller, Keith <[log in to unmask]> wrote: > >> I may be showing my ignorance here, but I would think that the fact that >> the five different lat longs all plotting at the same point showed that >> there WERE transformations taking place. If the “points” were supposed to >> represent the same physical location on the earth, then they SHOULD all >> overlap, as long as you tell ArcGIS the proper coordinate system used, >> which is what it sounds like you did in the second step. The first step >> showed the problem with not having proper documentation, in that the same >> “point” showed up in five different places on the map. What am I missing? >> >> >> >> Sincerely, >> >> Keith Miller >> >> >> >> *From:* Northeast Arc Users Group [mailto:[log in to unmask]] *On >> Behalf Of *Christina Herrick >> *Sent:* Wednesday, October 10, 2018 10:49 AM >> *To:* [log in to unmask] >> *Subject:* Re: Transforming xy data >> >> >> >> I'd be curious to know if anyone figures this out. I gave it a try and >> I'm also having the same issues. >> >> >> >> *Christina Herrick* >> >> Research Scientist >> >> V: 603.862.2639 | F: 603.862.0188 >> >> *University of New Hampshire* >> >> *Institute for the Study of Earth, Oceans, and Space* >> >> *Earth Systems Research Center* >> >> Morse Hall, 8 College Road >> <https://maps.google.com/?q=8+College+Road+%0D%0A+%0D%0A+Durham,+NH+03824&entry=gmail&source=g> >> >> <https://maps.google.com/?q=8+College+Road+%0D%0A+%0D%0A+Durham,+NH+03824&entry=gmail&source=g> >> >> <https://maps.google.com/?q=8+College+Road+%0D%0A+%0D%0A+Durham,+NH+03824&entry=gmail&source=g> >> >> Durham, NH 03824 >> <https://maps.google.com/?q=8+College+Road+%0D%0A+%0D%0A+Durham,+NH+03824&entry=gmail&source=g> >> >> >> >> ResearcherID: O-3375-2017 >> >> ORCID ID: 0000-0002-8384-9450 >> >> >> >> >> >> >> >> On Wed, Oct 10, 2018 at 10:19 AM Dan Martin - NOAA Federal < >> [log in to unmask]> wrote: >> >> Good morning, >> >> >> >> I will try to make this as understandable as possible: >> >> >> >> Objective: To show why proper metadata (datum/realization wise) is >> important. >> >> >> >> I got the datasheet for a geodetic control point in NJ. It has a current >> NAD 83(2011) lat/lon. It also has many superseded coordinates (Lat/Lon) >> going all the way back to NAD 83(1986). >> >> >> >> I created a map in ArcMap, and established the data frame coordinate >> reference to be NAD 83(2011) >> >> >> >> I then created a .txt file of the various NAD 83 positions that reflected >> the various realizations 2011, 2007, 1996, 1992, 1986. >> >> >> >> I added the xy data to the map and told ArcMap that they were Geographic >> NAD 83 (2011) (which of course they were not). As one would expect, I got >> 5 dots on the map with a spatial separation that reflected the differences >> between the 5 realizations. >> >> >> >> Next I created one file for each coordinate, and added each file one at a >> time. This time, I told ArcMap that the coordinate system for each file >> was actual realization of the position, i.e., when adding the NAD 83(2007) >> lat and lon, I told ArcMap that the coordinate system of the position was >> in fact NAD 83(2007). The result was 5 dots that plotted exactly on top of >> the other 5 dots, i.e., no transformation took place? >> >> >> >> Am I doing something wrong? >> >> >> >> Thanks for any input. I have attached the files if anyone wants to test >> this them selves. I have provided the files to some of my counterparts and >> they experienced the same. >> >> >> >> Dan >> >> >> >> >> Daniel J. Martin >> Northeast Regional Geodetic Advisor >> >> (ME, NH, VT, MA, CT, RI, NY, NJ) >> NOAA/NOS/National Geodetic Survey >> >> Email: [log in to unmask] >> >> Cell: 240-676-4762 >> >> >> >> ------------------------------------------------------------------------- >> This list (NEARC-L) is an unmoderated discussion list for all NEARC Users. >> >> If you no longer wish to receive e-mail from this list, you can remove >> yourself by going to http://s.uconn.edu/nearcsubscribe >> <https://urldefense.proofpoint.com/v2/url?u=http-3A__s.uconn.edu_nearcsubscribe&d=DwMFaQ&c=c6MrceVCY5m5A_KAUkrdoA&r=Fgp5Fj8BRI312O5a7XGOsE368byJfExS1LmNrumOv3s&m=SyeEl6O2EkDJ78lMtP_8EFzRH5GH_XbgF3TwR6spuyk&s=oal8vGy1_uILrcFkAnUZkoOWrBuCxHKSN5vV7OK_A30&e=>. >> >> >> ------------------------------------------------------------------------- >> This list (NEARC-L) is an unmoderated discussion list for all NEARC Users. >> >> If you no longer wish to receive e-mail from this list, you can remove >> yourself by going to http://s.uconn.edu/nearcsubscribe. >> ------------------------------------------------------------------------- >> This list (NEARC-L) is an unmoderated discussion list for all NEARC Users. >> >> If you no longer wish to receive e-mail from this list, you can remove >> yourself by going to http://s.uconn.edu/nearcsubscribe. >> > ------------------------------------------------------------------------- > This list (NEARC-L) is an unmoderated discussion list for all NEARC Users. > > If you no longer wish to receive e-mail from this list, you can remove > yourself by going to http://s.uconn.edu/nearcsubscribe. > -- Forrest J. Bowlick Graduate Program Director, MS Geography - GIST University of Massachusetts - Amherst Schedule a Meeting: meetme.so/UMassGIS ------------------------------------------------------------------------- This list (NEARC-L) is an unmoderated discussion list for all NEARC Users. If you no longer wish to receive e-mail from this list, you can remove yourself by going to http://s.uconn.edu/nearcsubscribe.