[Talk-ca] Map Error

Bob Dustan bob.dustan at gmail.com
Sun Oct 24 19:30:45 BST 2010


Hi,

I was importing CanVec data for 031E07 and noticed what appears to be an
error in the map.  A section of the Oxtongue River seems to be repeated
nearby in 031E06.  In OSM you can see it at:

http://www.openstreetmap.org/?mlat=45.317&mlon=-79.0&zoom=15&layers=M

If you use JOSM or Merkaator to view this area and enable the NRCan WMS,
you'll see that the error is also in the WMS version of the map.

The error also appears in "The Atlas of Canada" (Toporama) web site at:

http://atlas.nrcan.gc.ca/site/english/maps/topo/map?layers=nodata_ntdb_50k%20north_arrow%20other_features%20million_grid%20t50k_grid%20grid_50k_3%20roads%20hydrography%20boundary%20builtup%20vegetation%20populated_places%20railway%20power_network%20manmade_features%20designated_areas%20water_features%20water_saturated_soils%20relief%20contours%20toponymy%20contour&scale=1400000.000000&mapxy=1281552.5697346777%20-273673.4692181579&map_layer[northarrow]_class[0]_style[0]=ANGLE%20-14.587661326428645&mapsize=750%20666&urlappend=

The error also appears in the Ibycus map.

Also, if you look north along the boundary between these 2 map sections,
you will see other discrepancies.

I have topo maps of the area that I bought at least 10 years ago.  They
appear to be scans of paper maps.  When I line up the 2 map sections,
everything lines up (roads, rivers, elevation lines, etc.). 

It seems to me that some errors (albeit fairly minor) were introduced in
the digital form of the map.  Then the errors were propagated to CanVec.

Is there a way to get the map corrected?

Bob



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