For best accuracy you need several GPX traces of the area ideally recorded over several days to eliminate errors. Display all of these and drag the image into alignment with the average of the traces before mapping from any images. More information can be found here https://wiki.openstreetmap.org/wiki/Using_Imagery edt in response to question re gps/gpx A GPX file can only be recorded by surveying the area and recording your position with a GPS device, GPS equip smart phone or GPS dongle. A GPX trace should be accurate to +-5 metres and if you have several for the same area you can check and if required fix the image position. OSM as a database of traces. see https://wiki.openstreetmap.org/wiki/Upload_GPS_tracks and https://www.openstreetmap.org/traces You will be able to learn more by spending time reading the OSM WIKI

For best accuracy you need several GPX traces of the area ideally recorded over several days to eliminate errors. Display all of these and drag the image into alignment with the average of the traces before mapping from any images. More information can be found here https://wiki.openstreetmap.org/wiki/Using_Imageryhttps://wiki.openstreetmap.org/wiki/Using_Imagery edt in response to question re gps/gpx A GPX file can only be recorded by surveying the area and recording your position with a GPS device, GPS equip smart phone or GPS dongle. A GPX trace should be accurate to +-5 metres and if you have several for the same area you can check and if required fix the image position. OSM as a database of traces. see https://wiki.openstreetmap.org/wiki/Upload_GPS_tracks

For best accuracy it's best to have you need several GPX traces of the area ideally recorded over several days to eliminate errors. Display all of these and drag the image into alignment with the average of the traces before mapping from any images. More information can be found here https://wiki.openstreetmap.org/wiki/Using_Imagery

For best accuracy it's best to have several GPX traces of the area ideally recorded over several days to eliminate errors. Display all of these and drag the image into alignment with the average of the traces before mapping from any images. More information can be found here https://wiki.openstreetmap.org/wiki/Using_Imagery

For best accuracy it's best to have several GPX traces of the area ideally recorded over several day days to eliminate errors. Display all of these and drag the image into alignment with the average of the traces before mapping from any images.

For best accuracy it's best to have several GPX traces of the area ideally recorded over several day to eliminate errors. Display all of these and drag the image into alignment with the average of the traces before mapping from any images.