CDED data can be used in the generation of three-dimensional graphics displaying terrain slope, profiles and line of sight. The following is copied from cded_086e08_1_0_fgdc_en.xml Product Specifications, Edition 2.1, October 2005. This product is subject to discrepancies detection process. A discrepancy is defined as any deviation of dataset (or metadata) from the product's Standards and Specifications. For information on detected discrepancies refer to the discrepancy section for this product on host Web portal. Minimum Elevation (Z) in meters: 180 Maximum Elevation (Z) in meters: 305 The following steps were undertaken to generate CDED derived from 1:50,000 NTDB source data: 1) Flow directionality is applied to the stream coverage using the lake and contour data (arcs pointing downstream), maintaining a connected hydrographic network. 2) Incongruities in the NTDB hydrography and hypsography including the problems in the edgematching with the 8 surrounding tiles are identified and corrected. 3) Elevations on lake polygons corresponding to the lake elevations recorded on the paper map are tagged. 4) A DEM using ANUDEM version 5 with hydrographic network, contours, and elevation points as input data, are produced. 5) Quality Control on the DEM is conducted. 6) The DEM is converted to CDED format. For the final CDED, an automatic inspection is conducted by the Centre for Topographic Information Sherbrooke prior to archiving. Contact CTI for spectific information about this dataset.

CDED data can be used in the generation of three-dimensional graphics displaying terrain slope, profiles and line of sight. The following is copied from cded_086e08_1_0_fgdc_en.xml Product Specifications, Edition 2.1, October 2005. This product is subject to discrepancies detection process. A discrepancy is defined as any deviation of dataset (or metadata) from the product's Standards and Specifications. For information on detected discrepancies refer to the discrepancy section for this product on host Web portal. Minimum Elevation (Z) in meters: 180 Maximum Elevation (Z) in meters: 305 The following steps were undertaken to generate CDED derived from 1:50,000 NTDB source data: 1) Flow directionality is applied to the stream coverage using the lake and contour data (arcs pointing downstream), maintaining a connected hydrographic network. 2) Incongruities in the NTDB hydrography and hypsography including the problems in the edgematching with the 8 surrounding tiles are identified and corrected. 3) Elevations on lake polygons corresponding to the lake elevations recorded on the paper map are tagged. 4) A DEM using ANUDEM version 5 with hydrographic network, contours, and elevation points as input data, are produced. 5) Quality Control on the DEM is conducted. 6) The DEM is converted to CDED format. For the final CDED, an automatic inspection is conducted by the Centre for Topographic Information Sherbrooke prior to archiving. Contact CTI for spectific information about this dataset.