7
votes
1answer
136 views

What are the pros and cons of forcing square pixels on reprojection?

I am using Erdas Imagine 2014 to reproject 4-band raster data from GRS 1980 NAD83 Lambert Conformal Conic (ft) to UTM GRS 1980 NAD83 North UTM Zone 11 (m). Unlike ArcGIS, Erdas provides the option to ...
3
votes
1answer
304 views

Which Geographic Transformation to use for WGS_84 to D_Sphere?

I have a shapefile for world countries and I want to reproject it from GCS_WGS_1984 to Sphere_Eckert IV. However, it asks for Geographic Transformation; it says this is optional but it is required in ...
0
votes
1answer
503 views

Arcgis shape file and EPSG code

Why a shape file with CRS WGS_1984_UTM_Zone_22N en Arcgis has a differrent prj file than the EPSG:32622:WGS 84 / UTM zone 22N WKT ? Can I replace Arcgis .prj file with EPSG:32622 WKT ...
5
votes
1answer
141 views

What projection is this and how to use it in a GIS?

I have a request to do a map in non-standard projection: (source: http://www4.agr.gc.ca/AAFC-AAC/display-afficher.do?id=1263246127905&lang=eng) I couldn't manage to find it my materials. As well ...
6
votes
2answers
5k views

Which coordinate system and projection shall I use for georeferencing google map image in ArcGIS?

I have saved Google Maps image (not Google Earth) of area at latlon(17.692437,83.218689) by some method in jpeg format. It is an exact snapshot of the Google Maps. Now I need to geo-reference it to ...
9
votes
1answer
6k views

Which is the correct projection in ArcGIS for EPSG:3857/900913?

I want to publish a mapservice in ArcGIS server, which will be overlayed on Google Maps or Bing Maps. For this, the Map Service needs to be in EPSG:3857/900913. The Google Maps projection is supposed ...
2
votes
1answer
255 views

Convert map to use space oblique mercator projection

I have a map document in ArcMAP which I want to convert to using Space oblique mercator projection, but not sure if ArcMap supports it. Any hints on how to achieve this? thanks!
2
votes
2answers
308 views

projection issues from ArcGIS to Qgis

I am pretty new to ArcGIS and Qgis. I have loaded some geometry data in Qgis from my postgres database, then I have also loaded the same data in ArcGIS. Then from ArcGIS i have created a shapefile ...
2
votes
2answers
317 views

How to calculate the surface using Lambert correction?

i'm using lambert conformal conic , so we have distortions along any given parallel , i would like to get the area used to solve this distortion. I have calculated the area using Shoelace formula , ...
2
votes
2answers
208 views

How to project US States in Transverse Mercator [duplicate]

Possible Duplicate: Layers having the same coordinate system should overlap, but they don’t. What’s wrong? I created two different MXDs, one for City of Tucson and another for US States. If ...
4
votes
2answers
1k views

Create custom projection using either QGIS (or ArcGIS)?

I have searched for an answer to this but don't see anything relating to what I am trying to do. What I have are a series of Geographic Coordinates, Latitude, Longitude, Ellipsoid heights. What I ...
7
votes
5answers
3k views

Calculate distance in km to nearest points (given in lat/long) using ArcGIS

I have two point datasets in ArcGIS, both of which are given in WGS84 lat/lon co-ordinates and the points are spread across the whole world. I would like to find the nearest point in Dataset A to each ...
2
votes
1answer
779 views

Convert shapefile in NAD27 from meters to decimal degrees to match xy data?

I have a shapefile of a boundary (polygon) that has the following projection: NAD_1927_UTM_Zone_11N Projection: Transverse_Mercator False_Easting: 500000.00000000 False_Northing: ...
5
votes
3answers
1k views

Using arcpy what is the most efficient way of projecting a selection from a large data set?

I have a large data set X(x1-xn) from which I must select consecutively the attributes A(a1-an) from X.fieldsSRC or X.fieldDST and project the selections. I have a functioning arcpy script that does ...
0
votes
1answer
773 views

I can project from UTM (zone 10) into State Plane (Oregon), but I can't do the reverse — why not?

I have an air photo with the following xy coordinate system name: NAD_1983_StatePlane_Oregon_North_FIPS_3601_Feet_Intl and the following in the description field: Projection: ...
1
vote
2answers
4k views

How to create custom coordinate system in ArcGIS?

I have a series of control points with xy coordinates in both NAD83 UTM and in a local grid. How can I go about creating a new projection file in ArcGIS 10 for the local grid? Thanks
2
votes
1answer
948 views

How can I transform GCS_WGS_1984 to GCS_North_American_1983?

I need to convert a GCS_WGS_1984 data set to NAD_1983_UTM_Zone_14N. What transformation should I use?
1
vote
1answer
312 views

Best practices to minimize error when buffering unprojected data

If I buffer hundreds of unprojected WGS84 points across the US by say, 3 miles, will I get accurate areas returned (3 x pi x r) for each of the circles created? I suspect not. If not, what would be ...
4
votes
2answers
384 views

How to efficiently project datasets of varying coordinate systems into one coordinate system?

I am working on streamlining data processing at my organization. Currently we are using various large-scale Models that we will gradually bring into Python. The gist of our data processing is as ...
8
votes
2answers
539 views

What happens to a feature class when importing to a feature dataset?

I am creating a model that needs to ensure that all input datasets end up in the same coordinate system (among other things). I was originally going to batch project all of the datasets whether they ...
3
votes
2answers
1k views

How to set spatial reference to OSGB_1936_British_National_Grid in ArcGIS

I have two datasets in ArcGIS. One is from the Ordnance Survey (UK National Mapping Agency) and, when I view the properties of the dataset it says that the Spatial Reference is ...
2
votes
1answer
300 views

Reproject TM65 to OSGB in ArcGIS

I have a TIFF file in the TM65 (Transverse Mercator) projection, and want to convert it to the OSGB (British National Grid) projection. I'm trying to do this in ArcGIS using the Project Raster tool. ...
2
votes
1answer
86 views

Coords not aligning

The two shp files are not aligning like they should (note the img). The layer and the two shps all have the same coords - NAD_1983_StatePlane_North_Dakota_North_FIPS_3301_Feet The surface shp came ...
2
votes
4answers
8k views

I'm having trouble with getting a shapefile in the right projection. What am I doing wrong?

I have an older map that I didn't create. I'm just trying to get everything to line up on it, and having a hard time. The data frame is in NAD_1927_UTM_Zone_12N, as are the point shapefiles (derived ...
6
votes
1answer
8k views

How can I transform GCS_North_American_1983 to GCS_WGS_1984?

I posted a thread today describing a shift in some of the NRC data (not all). Apparently, this shift has to do with conversion between Geographic coordinates, latitude and longitude and Transverse ...
6
votes
2answers
1k views

ArcGIS 10 British National Grid Transformation

In ArcGIS 10 a new transformation has been added for converting between WGS84 and British National Grid. What is OSGB_1936_To_WGS_1984_NGA_7PAR? How should it be used when compared with the other ...
2
votes
1answer
641 views

I have several layers (polylines and polygons) that are of the same area but they don't overlap in ArcMap as they should, what do I do?

For my GIS project for my class, I have downloaded several vector layers from different websites (polyline of the continental divide, a boundary polygon of New Mexico, a rivers and water bodies layer ...
1
vote
1answer
946 views

How to convert from ITM ref to GPS ref ?

How can I convert from ITM ref (Israel new map) to GPS ref and from GPS ref to ITM ref? I need any C# sample code or formula for this. For example: 32.086156,34.769239 = 178364,665948 Or : ...
5
votes
2answers
253 views

Arcmap: Create a projection to emphasize a given direction?

Suppose one had a dataset (centered on a given coordinate) of lines that were very close together in terms of longitude but also had important turns/bends far separated by latitude. In order to map ...