topic Re: CAD Map scale off in Arcmap in Mapping Questions https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97075#M1137 <HTML><HEAD></HEAD><BODY><P>Ok. So both drawings need to be to the same scale to georeferenc correctly then?</P><P></P><P>Sent from my iPhone</P></BODY></HTML> Fri, 18 Sep 2015 22:21:44 GMT BradHoffer 2015-09-18T22:21:44Z CAD Map scale off in Arcmap https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97069#M1131 <HTML><HEAD></HEAD><BODY><P>i'm sure the answer is simple and maybe i just need more coffee but I have georeferenced a cad jpeg of a blueprint into arcmap.&nbsp; Once I have digitized the features the total length of, lets call it a rectangle, measures out to 188 feet.&nbsp; The CAD drawing is at 205.&nbsp; I'm using a projected coordinate system and have been rattling my brain for hours.&nbsp; Any advice out there?&nbsp; Thanks all. </P><P></P><P>Brad</P></BODY></HTML> Fri, 18 Sep 2015 21:59:57 GMT https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97069#M1131 BradHoffer 2015-09-18T21:59:57Z Re: CAD Map scale off in Arcmap https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97070#M1132 <HTML><HEAD></HEAD><BODY><P>Are you sure your georeferenced jpg is good..??? I'm not using arcgis to georeference images because is not very good. I prefer external tools like envi, erdas or global mapper, more suitable to manage large images</P></BODY></HTML> Fri, 18 Sep 2015 22:05:28 GMT https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97070#M1132 NICOLAPEDDIS 2015-09-18T22:05:28Z Re: CAD Map scale off in Arcmap https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97071#M1133 <HTML><HEAD></HEAD><BODY><P>I thought the same thing. I tested that idea by just pulling the the image into arc and measure it before georeferencing and it still measure out short.</P><P></P><P>Sent from my iPhone</P></BODY></HTML> Fri, 18 Sep 2015 22:08:32 GMT https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97071#M1133 BradHoffer 2015-09-18T22:08:32Z Re: CAD Map scale off in Arcmap https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97072#M1134 <HTML><HEAD></HEAD><BODY><P>It's far to easy to georeference an image incorrectly if quality is important, ask for the "dwg" file in a known coordinate system</P></BODY></HTML> Fri, 18 Sep 2015 22:10:51 GMT https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97072#M1134 WesMiller 2015-09-18T22:10:51Z Re: CAD Map scale off in Arcmap https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97073#M1135 <HTML><HEAD></HEAD><BODY><P>I have no known coordinate system for the dwg</P><P></P><P>Sent from my iPhone</P></BODY></HTML> Fri, 18 Sep 2015 22:13:20 GMT https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97073#M1135 BradHoffer 2015-09-18T22:13:20Z Re: CAD Map scale off in Arcmap https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97074#M1136 <HTML><HEAD></HEAD><BODY><P><SPAN class="replyToName">Brad, the coordinate system is not a problem, you can easly assign the coordinate system after you georeferenced a image, but you have to sure the initial scale of the original drawing to apply correctly the georeference</SPAN><STRONG class="font-color-meta"><SPAN class="replyToName"><BR /></SPAN></STRONG></P></BODY></HTML> Fri, 18 Sep 2015 22:18:45 GMT https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97074#M1136 NICOLAPEDDIS 2015-09-18T22:18:45Z Re: CAD Map scale off in Arcmap https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97075#M1137 <HTML><HEAD></HEAD><BODY><P>Ok. So both drawings need to be to the same scale to georeferenc correctly then?</P><P></P><P>Sent from my iPhone</P></BODY></HTML> Fri, 18 Sep 2015 22:21:44 GMT https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97075#M1137 BradHoffer 2015-09-18T22:21:44Z Re: CAD Map scale off in Arcmap https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97076#M1138 <HTML><HEAD></HEAD><BODY><P>Yes the same scale its an important prerequisite to do a good job.</P><P>After you have both files at the same scale, and you are sure the scale reflect the real space between the objects you can digitize your new objects.</P><P>You can use google earth&nbsp; to see the real scale of the dwg, if you know really where the dwg come from</P></BODY></HTML> Fri, 18 Sep 2015 22:29:38 GMT https://community.esri.com/t5/mapping-questions/cad-map-scale-off-in-arcmap/m-p/97076#M1138 NICOLAPEDDIS 2015-09-18T22:29:38Z