Latest Contributions by MelitaKennedy

‎08-30-2016

What's the data frame's coordinate system? And the raster's extent after the define projection? Thanks! Melita

‎08-29-2016

Even though they say it's in Mercator, there's a bunch of north-south distortion at those latitudes. The Y range is almost 3 times the X range in Mercator (approximately--I didn't use the sphere values) so as Darren demonstrated, it looks like the raster is really in lat/lon (geographic CRS). I'm also attaching a Panorama prj file. You would script in a call to Define_Projection to set this coordinate system. You may need to also define a transformation to pick up the difference between the sphere and WGS84. You can use the Create Custom Geographic Transformation tool. Use the geocentric translation method and leave the parameter values set to zeroes. You might also query the data provider for the "regional molodenky transformation values." If the sphere model is earth-centered, the Molodensky parameters should be zeroes unless they're making some other kind of adjustment. Melita

‎08-26-2016

It'll depend on the schedule of Runtime, and the Esri projection engine. New coordinate systems and transformations are added to the projection engine first (pe.dll or jpe_sdk.jar), then other Esri software packages incorporate the new library. For instance, if someone got me the definitions within the next few weeks, I could probably get the them into ArcGIS 10.5 (Desktop/Server), otherwise, depending on when they're available next year, possibly ArcGIS 10.5.1. Runtime's schedule is a little different. We have think about whether we let an SDK that's can be used to build client software have definitions that aren't yet available in the Server software. To request additions, contact technical support, or me (mkennedy at esri), but it's a lot easier to track if it goes through technical support. In parallel, or I can forward the information, submit to the IOGP's geodesy subcommittee which maintains the EPSG Geodetic Parameter Registry. Projected CRS names projection and parameter values unit (meters and feet?) Geographic CRS exents, both rectangular and polygon Agency Source Melita

‎08-26-2016

A guess on my part, because I haven't been involved with ArcPad for a while. The coordinates look like Web Mercator (EPSG:3857). Is there a base map? that's likely in 3857, and the data points may be getting projected to that coordinate system. I don't know how to change it.

‎08-26-2016

Thank you, David! Those are decimal degree values, so the data's in NAD 1983 (4269 is the well-known ID, WKID). I'm not sure how it ended up with a Hawaii Albers definition! Either use the Define Projection tool, or the data's property page in Catalog to update the coordinate system. This will update the metadata only, not the coordinate values. Hope this helps! Melita

‎08-26-2016

Hi David, Is the location you downloaded the data from public? That is, can you post the location so someone else can try downloading the data? Also, would you mind sharing the extent of the original data? If you add the data to a new ArcMap and don't change the data frame's coordinate system, what are the extents as you check the edges of the data? If I add the Esri topographic base map (EPSG:3857), and change the data frame's coordinate system to Hawaii Albers, the extents of the lower 48 are (very roughly!): x min: 2950000 m y min: 2060000 x max: 8400000 y max: 5000000 (As far as I know, US census data is almost always in geographic, latitude-longitude).

‎08-24-2016

Just double-checking that you used the Project tool and not the Define Projection Tool. How are you checking it against Google Maps?

‎08-17-2016

Hi Julie, Either use the Project or Project Raster tool. In the tool for the output coordinate system, you should be able to type in the well-known ID of the UTM zone, 32634, or browse to projected coordinate systems, UTM, WGS 1984 (North). For the geographic transformation, use ETRS_1989_To_WGS_1984. Melita

‎08-15-2016

Are you looking for which geographic/datum transformation to use to convert from MGI to WGS84? You'll need to use a concatenated transformation. Try MGI_To_ETRS_1989_5 + ETRS_1989_To_WGS_1984. Note: the first transformation uses the NTv2 file, AT_GIS_GRID.gsb. For some reason, we didn't put in transformation that converts directly from MGI to WGS84 and uses the NTv2 file. I plan to add one in a future release. Melita

‎08-05-2016

Did you get a program code from NGA? If so, try entering it on this web page: ELA-HUP If instead, NGA will reimburse you, try this website: ArcGIS for Personal Use Program | ArcGIS for Desktop Advanced for Personal Use Melita

‎08-04-2016

What transformation did you use? We have several Bogota to WGS84 transformations, but only one is for the entire country: Bogota_To_WGS_1984. The Bogota_To_WGS_1984_2 is for a few oil fields, and the others are for various districts, not the entire country. Bogota_To_WGS_1984 is not a particularly accurate transformation, maybe 10 m. You might also try one of the "Region VIII" transformations. Region VIII covers the eastern half of the country to see if gives a better overall fit. Melita

‎08-01-2016

There's been a few threads over on CartoTalk. One had no answers. The other mentioned ProMapper and Manifold. I'm sure it's come up here or on the previous Esri forums, but ArcGIS is not set up to extend beyond 360 degrees. Melita

‎07-28-2016

<psst> "longitude" in western hemisphere

‎07-28-2016

It's possible whatever software was used to generate the original image calculated the scale bar at the equator (ArcMap used to do this; I don't know if it still does), rather than at 47N. I get 0.68% reduction east-west ( cos(47) ) which ends up being 34 km / 50 km. If it was a bathymetry chart, it could be using Mercator with a standard parallel set around 47N to reduce distortion. That would also give a rectangular graticule. Melita

‎07-28-2016

No, ArcMap can't do that type of wrapped effect. You might be able to do something similar with separate data frames, but it would be difficult with van der Grinten because we usually don't allow data to go outside the projection's "horizon"--its valid area of use. Part of that includes not having the same point map/convert to two different places! Melita

My Ideas

Latest Contributions by MelitaKennedy

Re: Converting raster XY co-ordinates to lat/long

Re: Converting raster XY co-ordinates to lat/long

Re: Adding projected coordinate systems

Re: ArcPad 10.2 Coordinates Problem

Re: Reprojecting to Web Mercator

Re: Reprojecting to Web Mercator

Re: Reprojecting to Web Mercator

Re: MGI m31 to WGS 84 utm 33N which method?

Re: MGI m31 to WGS 84 utm 33N which method?

Re: Home Use Program NGA

Re: How can I transform my projection system Colombia Bogota zone to WGS84?

Re: World Map

Re: Points created in excel keep projecting at the equator

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