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    This group of maps, which includes the CanMatrix and CanTopo collections, is now a legacy product that is no longer maintained. It may not meet current government standards. Natural Resources Canada's (NRCan) topographic raster maps provide a representation of the topographic phenomena of the Canadian landmass. Several editions of paper maps have been produced over time in order to offer improved products compared to their predecessors in terms of quality and the most up to date information possible. The georeferenced maps can be used in a Geographic Information System (GIS). In all cases, they accurately represent the topographical data available for the date indicated (validity date). The combination of CanMatrix and CanTopo data provides complete national coverage. • CanMatrix - Print Ready: Raster maps produced by scanning topographic maps at scales from 1:25 000 to 1:1 000 000. This product is not georeferenced. Validity dates: 1944 to 2005 (1980 on average). Available formats: PDF and TIFF • CanMatrix - Georeferenced: Raster maps produced by scanning topographic maps at scales of 1:50 000 and 1:250 000. These maps are georeferenced according to the 1983 North American Reference System (NAD 83). Validity dates: 1944 to 2005 (1980 on average). Available format: GeoTIFF • CanTopo: Digital raster maps produced mainly from the GeoBase initiative, NRCan digital topographic data, and other sources. Approximately 2,234 datasets (maps) at scale of 1:50 000, primarily covering northern Canada, are available. CanTopo datasets in GeoPDF and GeoTIFF format are georeferenced according to the 1983 North American Reference System (NAD 83). Validity dates: 1946 to 2012 (2007 on average). Available formats: PDF, GeoPDF, TIFF and GeoTIFF

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    [IS] Á níunda áratug síðustu aldar voru fluglínur fyrir bandarískar loftmyndir frá 1956-1961 (svokallaðar DMA myndir) teiknaðar á níu kort í mælikvarðanum 1:250 000. Fyrsta og síðasta myndnúmerið var skrifað á hverja fluglínu. Nú hafa kortin verið staðsett og fluglínurnar settar á vektor form þar sem númer myndanna kemur fram í eigindum. Í kjölfarið var gagnagrunnurinn (fluglínur og loftmyndir) endurskoðaður. Nýlegar skannanir á öllum DMA myndunum frá Bandaríkjunum voru rýndar og aukaupplýsingum bætt inn í töflur, svo sem dagsetningu ljósmynda, brennivídd linsu og flughæð. Fluglínurnar voru einnig flokkaðar eftir staðsetningu og nálægum dagsetningum í eigindina „svæði“. Svo kölluð brúun (e. interpolation) var framkvæmd á hverri fluglínu þegar þær voru endurskoðaðar. Fyrsta og síðasta ljósmyndin á hverri fluglínu er þekkt, og gengið út frá því að allar myndir milli þeirra væru teknar með reglulegu millibili. Áætluð staðsetningarnákvæmni er +/- 2 km. [EN] The flightlines from the American photographs from 1956-1961 (so called DMA images) were hand-drawn in the 1980s in nine maps in 1:250.000. Each flightline had the first and last image number written on it. These maps were georeferenced and the flightlines were digitized into vectors, writing the image number as attributes. Once this was finished, a revision of the database was made. The recent scans of all the DMA images from USA were inspected, and extra information was added into the table, such as the date of the photographs, the focal lenght and flight height. The flightlines were also grouped by location and nearby dates, into the attribute "area". Once the flightlines were revised, an interpolation was done for each flightline. Since the first and last photograph of each flightline was known, we interpolated each photograph within a flightline assuming that all the images were captured at a regular interval. The expected accuracy of the geolocation is +/- 2 km.