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1h
comment How do I convert ESRI X,Y to Lat, Long for Google Maps?
Looks like NAD83 state plane New York Long Island using US survey feet, EPSG:2263.
5h
comment Defining the azimuthal equidistant projection of an Environment Canada weather radar map
Nothing I know about. You might be able to get NR Canada to give you the general extents.
5h
comment Defining the azimuthal equidistant projection of an Environment Canada weather radar map
@AndreJ Good comments! I tried to incorporate them into the answer.
5h
revised Defining the azimuthal equidistant projection of an Environment Canada weather radar map
incorporated more information based on AndreJ's comment.
7h
reviewed Approve Defining the azimuthal equidistant projection of an Environment Canada weather radar map
7h
answered Defining the azimuthal equidistant projection of an Environment Canada weather radar map
1d
comment Finding out points overlapping with another polygon shape file
Your files in dropbox aren't complete, unless you've renamed the file extensions. A shapefile, at minimum, needs .shp, .shx, .dbf and hopefully has .prj. All you posted are the .shp files. If you add both shapefiles to QGIS display, do they overlay?
1d
comment Projection issues whilst opening shapefile in ArcMap created in QGIS
QGIS uses GDAL/PROJ.4 for coordinate system support. PROJ.4 uses regular Mercator projection (ellipsoid-based) with a sphere definition to emulate EPSG:3857. The prj being written out by QGIS (GDAL) has a regular WGS84 GCS and Mercator as the map projection. The "sphere" definition is in an EXTENSION or PARAMETER or similar keyword which isn't read by ArcGIS.
1d
comment Projection For Measuring Distances
No projected CRS is great at not distorting distances. Even in equidistant conic, only the standard parallels and the longitude lines have correct distances. Using the geodesic method will give you true distances on the ellipsoid surface.
Jul
24
answered Polyconic Projection for China?
Jul
23
comment Finding angle to north on image with three control points
Which north? Geodetic north? Magnetic? Grid?
Jul
22
comment Coordinate Transformation Issues
Is the original point, in lat/lon, correct?
Jul
17
comment ArcMap Point Distance giving decimal degrees even when in projected coordinate system
Your xy data is still in latitude-longitude values aka a geographic coordinate system. You need to define back to NAD83 and use the Project Tool to create a new feature class (shapefile) that using NAD83 UTM 14N. AND don't use NAD83 (2011), that's valid in USA only. Just use NAD 1983.
Jul
16
comment How can I generate a properly-aligned shape from a land survey description?
From the OP's description, he has metes-and-bounds which is local, planar coordinates. Vincenty (geodesic) is overkill. @Marty What coordinate system is the PLSS section corners in? NAD83 (lat-long)?
Jul
16
comment What CRS is the USGS Global Land Cover Characteristics Data Base?
You would have to make a custom definition because none of the existing ones use arc-seconds. It would be based upon NAD83 using GRS80 ellipsoid. I found an older issue in Proj.4 about adding the ability to set the angular unit, so I'm not sure if it's supported.
Jul
16
comment ArcMap Point Distance giving decimal degrees even when in projected coordinate system
Did you use the Project tool to convert the data to zone 14 North? If you look at the data extents (in a new arcmap--don't set anything), what are they?
Jul
13
comment Is nearest search done on Euclidean plane accurate
But what plane? That is, in what projected coordinate reference system are you storing the data? If it's rectangular, like Mercator or cylindrical equal area, think about how much east-west distortion there is as you move away from the equator.
Jul
13
answered DotSpatial problems with reprojecting shape files
Jul
13
comment DotSpatial problems with reprojecting shape files
Well, the original prj files doesn't have the transformation info, so dotSpatial must be identifying the prj wkt as equivalent to the defn you posted. I think you'll have to modify the tmpShape.ProjectionString. You might check for a resource file and see if you can identify the bad entry.
Jul
13
comment DotSpatial problems with reprojecting shape files
Thanks for posting the PROJ.4 string. I think the +towgs84 is wrong. The 4th - 6th values should be in arc-seconds and the 7th in parts per million. Here's what they should be: -0.40685733, 0.35073268, -1.87034738, and 4.0812.