Re: [Qgis-user] Measurement tool
On Sat, 3 Nov 2018 at 01:54, Martin Weis wrote: > > Am 02.11.18 um 13:36 schrieb Josh Hull: > > inaccurate measurement when I am measuring both area and straight line > > > and its using WGS 84 / Pseudo-Mercator. I primarily use the software for > > maps in north central United States. > > Pseudo-mercator might be your issue here, it might have large > distortions, since your region is far away from equator. > Consider using UTM for metric units and measurements. I suspect this is the issue - psuedo mercator is totally unsuitable for any distance/area measurements. Try using QGIS 3.4.1 and comparing the area/distances using the identify tool on features. This will report both an ellipsoidal based area/distance calculation and direct cartesian calculation (using psuedo mercator in your case). You'll see huge discrepancies between the values. The real solution is to use an appropriate, well selected local projection, which is deemed suitable for distance and area measurements within your area of interest. Finding out what projection this is is left as an exercise for the reader ;) Nyall > > And have a look for the CRS of your project,according to: > https://docs.qgis.org/2.8/en/docs/user_manual/introduction/general_tools.html#measuring > ___ > Qgis-user mailing list > Qgis-user@lists.osgeo.org > List info: https://lists.osgeo.org/mailman/listinfo/qgis-user > Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Measurement tool
Am 02.11.18 um 13:36 schrieb Josh Hull: > inaccurate measurement when I am measuring both area and straight line > and its using WGS 84 / Pseudo-Mercator. I primarily use the software for > maps in north central United States. Pseudo-mercator might be your issue here, it might have large distortions, since your region is far away from equator. Consider using UTM for metric units and measurements. And have a look for the CRS of your project,according to: https://docs.qgis.org/2.8/en/docs/user_manual/introduction/general_tools.html#measuring ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Measurement tool
Hi, Distances depend on the WGS84 ellipsoid. Some tools don’t take that in consideration. What tools are you using? Nicolas > Le 2 nov. 2018 à 08:36, Josh Hull a écrit : > > I'm having problems with the measurement tool. It is giving me an > inaccurate measurement when I am measuring both area and straight line > distance. I'm currently running QGIS 3.4 because the problem started in > 3.2.3 and I thought upgrading might solve the issue. I'm running windows > 10, 64bit and installed from the standalone installer. I use shape file > overlays of property lines that have been rock solid for the past couple > years. When I measure a 40 acre parcel of land with the area measurement > tool, QGIS tells me the area is over 83 acres. If I measure a straight > line distance along the side of a known 40 (it should be 1/4 mile), the > measurement tool shows .368 miles. I haven't made any changes to the CRS > and its using WGS 84 / Pseudo-Mercator. I primarily use the software for > maps in north central United States. > > Any help would be awesome. > > -- > Josh Hull > Hull Forest Products LLC > 218-349-9266 > www.forest.solutions > > ___ > Qgis-user mailing list > Qgis-user@lists.osgeo.org > List info: https://lists.osgeo.org/mailman/listinfo/qgis-user > Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Measurement tool
In File -> Properties -> General - are your measurements set to the proper distance/Area/ellipsoid? Sometimes that catches me off guard when I forget. Randy On 11/2/18 8:36 AM, Josh Hull wrote: I'm having problems with the measurement tool. It is giving me an inaccurate measurement when I am measuring both area and straight line distance. I'm currently running QGIS 3.4 because the problem started in 3.2.3 and I thought upgrading might solve the issue. I'm running windows 10, 64bit and installed from the standalone installer. I use shape file overlays of property lines that have been rock solid for the past couple years. When I measure a 40 acre parcel of land with the area measurement tool, QGIS tells me the area is over 83 acres. If I measure a straight line distance along the side of a known 40 (it should be 1/4 mile), the measurement tool shows .368 miles. I haven't made any changes to the CRS and its using WGS 84 / Pseudo-Mercator. I primarily use the software for maps in north central United States. Any help would be awesome. -- Randal Hale rjh...@northrivergeographic.com https://www.northrivergeographic.com (423)653-3611 ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] Measurement tool
I'm having problems with the measurement tool. It is giving me an inaccurate measurement when I am measuring both area and straight line distance. I'm currently running QGIS 3.4 because the problem started in 3.2.3 and I thought upgrading might solve the issue. I'm running windows 10, 64bit and installed from the standalone installer. I use shape file overlays of property lines that have been rock solid for the past couple years. When I measure a 40 acre parcel of land with the area measurement tool, QGIS tells me the area is over 83 acres. If I measure a straight line distance along the side of a known 40 (it should be 1/4 mile), the measurement tool shows .368 miles. I haven't made any changes to the CRS and its using WGS 84 / Pseudo-Mercator. I primarily use the software for maps in north central United States. Any help would be awesome. -- Josh Hull Hull Forest Products LLC 218-349-9266 www.forest.solutions ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
