Linked Questions

11
votes
1answer
11k views

How to reproject a raster file in QGIS with datum transformation?

I want to reproject a tiff raster file from projection A (ETRS89/UTM Zone 32) to projection B (DHDN/Gauss-Kruger zone 2). The two projections have a different datum so I have to use a datum ...
6
votes
2answers
3k views

Layer misalignment with UK Ordnance Survey data and OpenLayers

I am in the UK and my QGIS projects are based on UK Ordnance Survey mapping data and are set up in EPSG:27700. Whenever I have tried dropping an OpenLayers layer (Google Satellite/Bing Maps Aerial) in ...
5
votes
1answer
265 views

How does QGIS reproject data?

Projection systems are always troubling and I cam across and issue yesterday. I created a buffer and did a select by location using that buffer, however it was producing the wrong results. It would ...
4
votes
1answer
298 views

Differences in the longitude and latitude between a LiDAR DSM and an optical image

I've downloaded the UK's LiDAR elevation data (see below) in laz format for a specific region (Tewkesbury) from: http://environment.data.gov.uk/ds/survey#/download From that, a DSM (Digital Surface ...
3
votes
4answers
2k views

Issues using geographic and projected coordinate systems QGIS 2.0

I am having issues with QGIS 2.0.1 working between local projected coordinate systems (such as OSGB36, NAD83) and Geographic systems (such as WGS84). The stock answer I have been provided is 'load ...
3
votes
0answers
2k views

OSGB36 to WGS84 reprojection 'error' [closed]

I am a recent convert to QGIS. I have surveyed (and corrected) DGPS (vector point) data collected to OSGB36 (British National Grid); these positions match acceptably well with the OSGB36 map layers ...
2
votes
3answers
3k views

What are the differences between 81989 and 27700 CRS for the British National Grid?

We are using Oracle Spatial to run point in polygon queries in Great Britain using Ordnance Survey MasterMap and point data. MasterMap is on British National Grid (BNG) and has the Coordinate ...
2
votes
1answer
349 views

Partial loss of projection data converting to MapInfo File with OGR

I'm trying to convert some data from ESRI Shapefile to MapInfo TAB format using ogr2ogr. The data is projected using the British National Grid (EPSG:27700). The output file is valid, and the geometry ...
2
votes
1answer
1k views

proj/pyproj converted coordinates offset

I'm using pyproj to convert some coordinates from WGS84 to OSGB36. When mapped out the converted and unconverted don't map to the same places on a map. The OSGB36 coordinates are mapped about 100 ...
2
votes
0answers
674 views

MapInfo v QGIS British National Grid Projection

I have a question about the British National Grid (ESPG:27700) projection and how it's defined in both QGIS, ArcGIS and MapInfo. The go to GIS editor in my industry has been MapInfo. It seems however ...
2
votes
0answers
305 views

QGIS CRS correct, but layers appear warped

I am trying to overlay a raster Landsat 8 scene and vector scene boundary. Both are using WGS 84 + UTM48N. However, the vector (orange line) appears offset when overlaid on the raster. I have checked ...
1
vote
2answers
1k views

British National Grid to KML results in offset polygons

I have a shapefile of English wards from ONS. It is similar to the files available here: http://www.ons.gov.uk/ons/guide-method/geography/products/census/spatial/2011/index.html except I had to ...
1
vote
0answers
510 views

problem overlaying osm with os-derived data in QGIS - both British National Grid

I am currently working alongside city council datasets derived from Ordnance Survey; this is projected in their ArcSDE system as "British National Grid" or EPSG:27700. My problem is that I am trying ...
1
vote
0answers
90 views

Problems with CRS in Qgis [duplicate]

Possible Duplicate: Raster incorrectly reprojected to OSGB(27700) The crs is clearly off when the gridlines run straight and the map lines run at an angle. I have set the crs to match the ...
0
votes
1answer
307 views

Reprojecting coordinates using gdalwarp and OpenLayers?

I have an interpolated raster image with EPSG:27700 (British National Grid), after I warp it using gdalwarp into EPSG:3857 (WGS84 Web Mercator (Auxiliary Sphere)): gdalwarp -s_srs EPSG:27700 -t_srs ...