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I have a set of shapefiles for Europe which are in Lambert Azimuthal Equal Area (LAEA) projection: LAEA screenshot in ArcMap 10.4

I am working in the UK and have a list of points in British National Grid (BNG) projection (GCS_OSGB_1936).

I need to accurately display the BNG points on top of a grid (shapefile) that is in LAEA, and number the grid cells that contain a point.

In ArcMap 10.4 I have set the data frame (Layers) to BNG and so I can correctly display my points (and OS basemaps). When I add the LAEA layers there is a Geographic Coordinate Systems Warning with the following info (that provides no other options in the dropdown boxes):

transformation info screenshot

When I click 'close' the LAEA layers draw and look to be in vaguely the right location over the OS BNG data, but not exactly...

(The same happens in reverse if I set the data frame to LAEA and then try to add the BNG points)

If I try 'defining projection' of the BNG points and setting them to LAEA, then it ends up drawing them in the middle of Europe (definitely not correct!)

Can anyone suggest a way to ensure that my BNG points and LAEA grid are correctly aligned to one another?

Likewise if there is a way of converting the points directly from BNG to LAEA in Excel that would also be useful.

closed as unclear what you're asking by PolyGeo Jun 17 '17 at 7:35

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • Can you post the "spheroid" parameters? They're just below the CRS details that are showing in your screen-grab. Also, can you guesstimate how far off the two layers are now? Is it a mostly north-south offset? – mkennedy Dec 7 '16 at 20:32
  • On the first screenshot - there is one more line of info not captured in the screen grab which says: 'Angular Unit': 'Degree' is that what you need? – jess_n1 Dec 8 '16 at 12:03
  • Visually I'd say it looks like the LAEA layers are too far North (maybe 3km or so) and too far West (approx. 1.5km) - although this is difficult to tell precisely as I'm visually comparing a complex (wiggly) catchment outline against a 5 x 5 km grid version of the same catchment. – jess_n1 Dec 8 '16 at 12:13
  • My mistake, I thought the ellipsoid parameters were in that box. Open the data's property page in arccatalog and get them there, please. There's a couple possibilities and I'm trying to figure out which is the best to try! – mkennedy Dec 8 '16 at 14:34
  • Projection: Lambert_Azimuthal_Equal_Area false_easting: 0.0 false_northing: 0.0 central_meridian: 9.0 latitude_of_origin: 48.0 Linear Unit: Meter (1.0) Geographic Coordinate System: GCS_unnamed ellipse Angular Unit: Degree (0.0174532925199433) Prime Meridian: Greenwich (0.0) Datum: D_unknown Spheroid: Unknown Semimajor Axis: 6378388.0 Semiminor Axis: 6378388.0 Inverse Flattening: 0.0 – jess_n1 Dec 9 '16 at 11:30