Presentation on theme: "Introduction to GIS for Map Construction In this lesson you will learn: common raster and vector data exchange formats sources of raster and vector data."— Presentation transcript:
Introduction to GIS for Map Construction In this lesson you will learn: common raster and vector data exchange formats sources of raster and vector data map construction principles bringing data into the GIS – the map view scaling and projecting the GIS map formatting and outputting the map – the layout view
Raster data formats Generic raster data exchange formats: TIFF filename.tif JPEGfilename.jpg GIFfilename.gif BMPfilename.bmp Geographically-registered raster data exchange formats GEOTIFFfilename.tif - with world filefilename.tfw Compressed raster data exchange formats MrSIDfilename.sid - with geo-reference world filefilename.sdw Proprietary & specialty formats ERDAS (.lan,.gis,.img) ESRI Grid (.grd) Intergraph (.cot,.cit,.rle) National Image Transfer Format (.ntf) Uncompressed ASCII satellite image (.bsq,.bil,.bip)
Raster data sources Types of publicly available raster data 1.map products scanned maps digital maps 2.geospatial imagery aerial photography satellite remote sensing imagery aerial remote sensing imagery 3.non-spatial imagery
Raster data sources – imagery Potential sources of raster data 1.public domain data state-level geospatial data clearinghouses repository public libraries privately-sponsored geospatial data clearinghouses 2.fee licensed data source public agency (NASA, NIMA, USGS, United Nations, etc.) local government source contractor (aerial photography company, land surveyor, etc.) 3.contract data
Raster map products: 1. DRGs Portion of a Digital Raster Graphic, USGS 1:24,000 topographic map; downloaded from the Illinois State Geospatial Data Clearinghouse
Raster map products: 2. DOQs Lake County, IL DOQ; downloaded from the Illinois State Geospatial Data Clearinghouse
Raster map products: 3. DEMs GTOPO30 DEM raster image of the northeastern portion of North America. Source: Land Processes Distributed Active Archive Center, USGS.
Raster map products: 4. LU/LC Sample land use/land cover raster image produced by the USGS Regional Land Cover Characterization Project; derived from early 1990s 30-m Landsat Thematic Mapper data. Source: USGS,
Vector data formats 1.Generic spatial data exchange formats SDTS (spatial data transfer standard) Open GIS 2.de facto standard exchange formats SHP (ESRI) MS-Access 3.Proprietary & specialty formats E00 (ESRI); MAP (MapInfo); MGE (Intergraph) SDE (ESRI) Oracle Spatial
Vector map products: 1. DLGs Sample plot of DLG data showing political boundary (white), hydrography (blue) and transportation (tan) feature classes for Dancyville, TN. Source: USGS,
Vector map products: 2. SSURGO & NWI SSURGO soil polygons, from an portion of Marquette County, MI. Image courtesy of Michigan State University National Wetlands Inventory data, central Lake County, IL. Map image generated by Wetlands Mapper, a product of the U.S. National Map.
Vector map products: 3. TIGER/Line ® data Railroad, road, and hydrography Tiger/Line ® data, DuPage County, IL. Data courtesy of the U.S. Bureau of the Census,
Map construction principles Choose: map geography (content) map scale datum & coordinate system map projection Obtain, consistent with above: source material (maps, imagery, other data) permission to use source material
Assembling the data – the map view
Map view operations Zoom In Zoom Out Pan Measure distance Add Data Add feature class to legend
Setting map extent and feature scales
Setting the map view projection
Formatting the map for output – the layout view
Printing the map Sheet Sizewidthlengthunits A8.511inches B1117inches C1722inches D2234inches E3444inches A centimeters A centimeters A centimeters A centimeters A centimeters A centimeters Standard paper sizes
Exporting the map
What you have learned In this lesson you learned: Common file formats for raster data include: BMP, JPEG, GIF, TIFF, GEOTIFF, and MrSID. The world file associated with GEOTIFF or MrSID raster data provide the information necessary to geographically register the raster data. Common file formats for vector data include: SDTS, Open GIS, SHP, and MS-Access. Small- and intermediate-scale geospatial data produced by state and federal government agencies is often available through state sponsored geospatial data clearinghouses, or directly from the agency responsible for producing the data. Some of the types of raster data that are generally available, free, include: DRGs, DOQs, DEMs, and land use/land cover images. Publicly available vector data include: DLGs, SSURGO, NWI, and Tiger/Line data. Scale, projection, datum and coordinate system are just as critical to the choice of spatial data for GIS as they are for conventional mapping. The data used in any GIS project should either be copyright-free, or properly licensed to you for use. GIS maps are assembled, edited, and formatted in the map view window and cartographically rendered for final output in the layout window. The content of the layout window is dynamically linked to the map view, hence all map construction operations, including setting the projection, scale, geographic extent, and feature symbolization, are performed in the map view window. Maps produced in a GIS can be output to printer or plotter devices, or exported and saved as raster graphics files (BMP, JPEG, TIFF, etc.).