Latest Contributions by MelitaKennedy

We added DHHN2016 in version ArcGIS Desktop version 10.5.0. It should be available in all version of ArcGIS Pro. We have a transformation that converts between DHHN2016 and EVRF 2007. We do not support a German geoid model yet. Melita ... View more

We're adding the GCS to ArcGIS Pro 2.3 and ArcGIS Desktop 10.7.0. I think Collector just had a release so it should be in their next release. Michael Loconte   NGS has released grid files to convert between NAD83 (original), HARN, FBN, NSRS2007, and 2011. See NADCON 5.0 and/or the NGS Coordinate Conversion and Transformations Tool (NCAT). Melita ... View more

First, I would use NGS's online tools to quantify how much is the shift between HARN and 2011 in your area. We have the transformations from HARN to 2007 to 2011 using GEOCON v1 starting at 10.4 but you have to install the ArcGIS Coordinate System Data setup to get the files. You still might need to convert from HARN or 2011 to WGS84. Which transformations have you tried? Any to WGS84? NAD_1983_To_WGS_1984_1 is a null transformation (parameters are zeroes). Try WGS_1984_ITRF00_To_NAD_1983_HARN (don't redefine to 2011) or WGS_1984_ITRF00_To_NAD_1983_2011. Melita ... View more

It's almost certainly a GCS (datum) issue. 3 ft / 1 m offset is classic for a NAD83 (some realization) vs WGS84 difference. It's very difficult to figure out what's going on because it depends on the basemap(s) and your data's history, what GCS, which if any transformation was used to convert from NAD83 (realization) into WGS84. ... View more

The false easting/false northing values have to use the same linear unit as the projected coordinate system itself. The well-known text string is using international feet (1 ft = 0.3048 m) but the false easting value is defined in meters. ... View more

We are planning on implementing time-based transformations. Mostly it's figuring out how to incorporate the epoch parameter, intraframe files, etc. into the software. I don't know which release it will be in. If you want a transformation to show up in the geoprocessing environments, you have to update the core.xml file that's located in C:\Program Files\ArcGIS\Pro\Resources\Help\gp\Environments. It's a hard-coded list and doesn't pick up any custom transformations. An entry looks like: <GPCodedValueDomainProperty xsi:type="typens:GPCodedValueDomainProperty"> <Name>Adindan_To_WGS_1984_1</Name> <Value xsi:type="typens:GPString"> <Value>Adindan_To_WGS_1984_1</Value> </Value> </GPCodedValueDomainProperty> so it's not difficult to add entries. Make sure you run Notepad (or another edit program) as an Administrator, and you'll  have to restart ArcGIS Pro.  Is there more than one point in the feature class? We had a problem in the Project tools when there's only one point. Melita ... View more

I assume the center of the buffers are in the correct locations? If certainly looks like the buffer distance was treated as 1 degree, rather than 1 mile. Projected into Web Mercator (EPSG:3857), the north-south distance would get stretched because that's what Mercator does to maintain conformality (local angles/shapes). Maybe try something like: buffer(geometries=[Geometry(address['location'])],in_sr=4326,distances=[1],unit='Miles',out_sr=3857,buffer_sr=4326,geodesic=true) ... View more

You can reduce overall distortion by adding a scale factor, but your area of interest is small so it's really not needed. False easting and false northing parameters are used to keep all values positive or to differentiate between two similar projected coordinate systems that use different GCS, for instance. ... View more

It's all relative to the "natural" projected coordinate system origin. That's usually central meridian / longitude of center and latitude of origin / latitude of center. Just to confuse things, technically, in a 2 standard parallel Lambert conformal conic case, The natural origin is almost halfway between the two standard parallels, so what Esri calls the latitude of origin is actually the latitude of false origin! Anyway, let's think about a UTM zone like 11N. Its projection parameters are always the same: central meridian: -117.0 latitude of origin: 0.0 scale factor: 0.9996 false easting: 500000.0 false northing: 0.0 If we compare the XY coordinates of a particular place in a NAD27-based zone versus a NAD83-based one, the coordinates will differ by up to 200 meters north-south and maybe 20 m east-west. The majority of the north-south offset is because NAD27 and NAD83 use ellipsoids that have different sizes and shapes. Some of the offsets are also because the two ellipsoids are oriented differently if you compare their positions relative to the earth's center. This all means that the latitude-longitude values of a position is almost always different when checked in different geographic coordinate systems (datums). The XY (easting-northing) values are derived from the latitude-longitude values so it all starts from there. You could try this by creating some latitude-longitude points in a NAD83 shapefile. 1. Project the shapefile to the appropriate NAD83 UTM zone. 2. Copy the NAD83 shapefile and redefine it (Define Projection tool or data property page) to NAD27, then project it to NAD27 UTM. 3. Project the NAD83 UTM shapefile to NAD27 UTM. The shapefile points from (2) should differ from (1) a bit, and both should differ more to (3). Melita ... View more

So you'll convert the vertical surface into a horizontal one? If you have a known latitude-longitude of the rectangle, I would use that as the central meridian. Maybe even using stereographic or azimuthal equidistant instead, centered on the rectangle. Melita ... View more

Two things to check in your second workflow.  1. In Calculate Geometry, make sure to use the data frame's coordinate system 2. When you set the Transformation, make sure it's using the same transformation that was used in the Project Tool. Melita ... View more

Hi Vince,  I'm sorry that I didn't respond sooner. Which software and version? (Pro / ArcMap) If you have Pro, could you try it there too? Melita ... View more

Hmmm, I don't know. Another team handles labeling! Are you building the labels in the backwards Krovak or...? Melita ... View more