{"id":285,"date":"2015-11-20T17:26:19","date_gmt":"2015-11-21T00:26:19","guid":{"rendered":"https:\/\/blogs.ubc.ca\/advancedgis\/?page_id=285"},"modified":"2019-11-19T09:39:49","modified_gmt":"2019-11-19T16:39:49","slug":"map-projections","status":"publish","type":"page","link":"https:\/\/blogs.ubc.ca\/advancedgis\/schedule\/slides\/georeferencing\/map-projections\/","title":{"rendered":"Various Map Projection Concepts Illustrated"},"content":{"rendered":"<h4>Distances as measured on a Grid, the Ellipsoid, the Geoid and on the Ground<\/h4>\n<p>You should be aware that there are significant changes when converting distances from a UTM map to the equivalent ground distance when using NAD27 versus using NAD83, as mentioned below:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-125 aligncenter\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/Grid-Ground-Distances.gif\" alt=\"Grid Ground Distances\" width=\"432\" height=\"288\" \/><\/p>\n<h4>Basis upon which the Great Circle Distance Calculation is Derived (recalling how to determine the length of a circle).<\/h4>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-317\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/Great-Circle-Distance1-723x1024.gif\" alt=\"Great Circle Distance\" width=\"237\" height=\"336\" srcset=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/Great-Circle-Distance1-723x1024.gif 723w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/Great-Circle-Distance1-212x300.gif 212w\" sizes=\"auto, (max-width: 237px) 100vw, 237px\" \/><\/p>\n<h4>False Origin<\/h4>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-318\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/False-Origin-Wisconsin1.gif\" alt=\"False Origin Wisconsin\" width=\"594\" height=\"257\" \/><\/p>\n<h4>Surfaces, Orientations and Coincidences<\/h4>\n\n\t\t<style>\n\t\t\t#gallery-1 {\n\t\t\t\tmargin: auto;\n\t\t\t}\n\t\t\t#gallery-1 .gallery-item {\n\t\t\t\tfloat: left;\n\t\t\t\tmargin-top: 10px;\n\t\t\t\ttext-align: center;\n\t\t\t\twidth: 33%;\n\t\t\t}\n\t\t\t#gallery-1 img {\n\t\t\t\tborder: 2px solid #cfcfcf;\n\t\t\t}\n\t\t\t#gallery-1 .gallery-caption {\n\t\t\t\tmargin-left: 0;\n\t\t\t}\n\t\t\t\/* see gallery_shortcode() in wp-includes\/media.php *\/\n\t\t<\/style>\n\t\t<div id='gallery-1' class='gallery galleryid-285 gallery-columns-3 gallery-size-thumbnail'><dl class='gallery-item'>\n\t\t\t<dt class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/blogs.ubc.ca\/advancedgis\/5-trans\/'><img loading=\"lazy\" decoding=\"async\" width=\"150\" height=\"150\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Trans-150x150.jpg\" class=\"attachment-thumbnail size-thumbnail\" alt=\"\" aria-describedby=\"gallery-1-299\" srcset=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Trans-150x150.jpg 150w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Trans-300x300.jpg 300w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Trans.jpg 400w\" sizes=\"auto, (max-width: 150px) 100vw, 150px\" \/><\/a>\n\t\t\t<\/dt>\n\t\t\t\t<dd class='wp-caption-text gallery-caption' id='gallery-1-299'>\n\t\t\t\tTranverse Cylindrical Projection Surface\n\t\t\t\t<\/dd><\/dl><dl class='gallery-item'>\n\t\t\t<dt class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/blogs.ubc.ca\/advancedgis\/5-plane\/'><img loading=\"lazy\" decoding=\"async\" width=\"150\" height=\"150\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Plane-150x150.jpg\" class=\"attachment-thumbnail size-thumbnail\" alt=\"\" aria-describedby=\"gallery-1-297\" srcset=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Plane-150x150.jpg 150w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Plane-300x300.jpg 300w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Plane.jpg 400w\" sizes=\"auto, (max-width: 150px) 100vw, 150px\" \/><\/a>\n\t\t\t<\/dt>\n\t\t\t\t<dd class='wp-caption-text gallery-caption' id='gallery-1-297'>\n\t\t\t\tPlanar Projection Surface\n\t\t\t\t<\/dd><\/dl><dl class='gallery-item'>\n\t\t\t<dt class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/blogs.ubc.ca\/advancedgis\/5-secant\/'><img loading=\"lazy\" decoding=\"async\" width=\"150\" height=\"150\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Secant-150x150.jpg\" class=\"attachment-thumbnail size-thumbnail\" alt=\"\" aria-describedby=\"gallery-1-298\" srcset=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Secant-150x150.jpg 150w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Secant-300x300.jpg 300w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Secant.jpg 400w\" sizes=\"auto, (max-width: 150px) 100vw, 150px\" \/><\/a>\n\t\t\t<\/dt>\n\t\t\t\t<dd class='wp-caption-text gallery-caption' id='gallery-1-298'>\n\t\t\t\tSecant Cylindrical Projection\n\t\t\t\t<\/dd><\/dl><br style=\"clear: both\" \/><dl class='gallery-item'>\n\t\t\t<dt class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/blogs.ubc.ca\/advancedgis\/5-oblique\/'><img loading=\"lazy\" decoding=\"async\" width=\"150\" height=\"150\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Oblique-150x150.jpg\" class=\"attachment-thumbnail size-thumbnail\" alt=\"\" aria-describedby=\"gallery-1-296\" srcset=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Oblique-150x150.jpg 150w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Oblique-300x300.jpg 300w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Oblique.jpg 400w\" sizes=\"auto, (max-width: 150px) 100vw, 150px\" \/><\/a>\n\t\t\t<\/dt>\n\t\t\t\t<dd class='wp-caption-text gallery-caption' id='gallery-1-296'>\n\t\t\t\tOblique Cylindrical Projection Surface\n\t\t\t\t<\/dd><\/dl><dl class='gallery-item'>\n\t\t\t<dt class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/blogs.ubc.ca\/advancedgis\/5-cyl\/'><img loading=\"lazy\" decoding=\"async\" width=\"150\" height=\"150\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Cyl-150x150.jpg\" class=\"attachment-thumbnail size-thumbnail\" alt=\"\" aria-describedby=\"gallery-1-295\" srcset=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Cyl-150x150.jpg 150w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Cyl-300x300.jpg 300w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Cyl.jpg 400w\" sizes=\"auto, (max-width: 150px) 100vw, 150px\" \/><\/a>\n\t\t\t<\/dt>\n\t\t\t\t<dd class='wp-caption-text gallery-caption' id='gallery-1-295'>\n\t\t\t\tCylindrical Projection Surface\n\t\t\t\t<\/dd><\/dl><dl class='gallery-item'>\n\t\t\t<dt class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/blogs.ubc.ca\/advancedgis\/5-conical\/'><img loading=\"lazy\" decoding=\"async\" width=\"150\" height=\"150\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Conical-150x150.jpg\" class=\"attachment-thumbnail size-thumbnail\" alt=\"\" aria-describedby=\"gallery-1-294\" srcset=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Conical-150x150.jpg 150w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Conical-300x300.jpg 300w, https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Conical.jpg 400w\" sizes=\"auto, (max-width: 150px) 100vw, 150px\" \/><\/a>\n\t\t\t<\/dt>\n\t\t\t\t<dd class='wp-caption-text gallery-caption' id='gallery-1-294'>\n\t\t\t\tConical Projection Surface\n\t\t\t\t<\/dd><\/dl><br style=\"clear: both\" \/>\n\t\t<\/div>\n\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-302\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/Proj.gif\" alt=\"Proj\" width=\"519\" height=\"534\" \/><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<h4>Illustrations of different map projections<\/h4>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-303\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5-Conic.gif\" alt=\"5 Conic\" width=\"463\" height=\"342\" \/> <img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-307\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5mollw1.gif\" alt=\"5mollw~1\" width=\"540\" height=\"341\" \/> <img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-306\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5miller.gif\" alt=\"5miller\" width=\"540\" height=\"341\" \/> <img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-305\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5merca1.gif\" alt=\"5merca~1\" width=\"540\" height=\"341\" \/> <img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-308\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5peters.gif\" alt=\"5peters\" width=\"516\" height=\"333\" \/> <img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-304\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5cylmap.gif\" alt=\"5cylmap\" width=\"540\" height=\"341\" \/><\/p>\n<h4>The UTM Projection-based coordinate system<\/h4>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-310\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5utmzo1.gif\" alt=\"5utmzo~1\" width=\"743\" height=\"423\" \/> <img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-309\" src=\"https:\/\/blogs.ubc.ca\/advancedgis\/files\/2015\/11\/5utm1z1.gif\" alt=\"5utm1z~1\" width=\"289\" height=\"531\" \/><\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Distances as measured on a Grid, the Ellipsoid, the Geoid and on the Ground You should be aware that there are significant changes when converting distances from a UTM map to the equivalent ground distance when using NAD27 versus using NAD83, as mentioned below: Basis upon which the Great Circle Distance Calculation is Derived (recalling [&hellip;]<\/p>\n","protected":false},"author":18620,"featured_media":0,"parent":116,"menu_order":3,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-285","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/blogs.ubc.ca\/advancedgis\/wp-json\/wp\/v2\/pages\/285","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.ubc.ca\/advancedgis\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/blogs.ubc.ca\/advancedgis\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.ubc.ca\/advancedgis\/wp-json\/wp\/v2\/users\/18620"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.ubc.ca\/advancedgis\/wp-json\/wp\/v2\/comments?post=285"}],"version-history":[{"count":7,"href":"https:\/\/blogs.ubc.ca\/advancedgis\/wp-json\/wp\/v2\/pages\/285\/revisions"}],"predecessor-version":[{"id":3271,"href":"https:\/\/blogs.ubc.ca\/advancedgis\/wp-json\/wp\/v2\/pages\/285\/revisions\/3271"}],"up":[{"embeddable":true,"href":"https:\/\/blogs.ubc.ca\/advancedgis\/wp-json\/wp\/v2\/pages\/116"}],"wp:attachment":[{"href":"https:\/\/blogs.ubc.ca\/advancedgis\/wp-json\/wp\/v2\/media?parent=285"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}