Correct me if I am wrong. There is a lot about this I do not know.
If I do not make use of the Choose KMZ function, nor the Import a File function when Creating a KLM Course - but set my course directly on the Satellite view of the world - I believe this method lets me make use of a map of NON URBAN terrain which is neither geo-referenced or particularly accurately drawn....as there is no reference to the actual OCAD map in the process of setting the course. The course can later be designed on P. Pen for printing purposes. The runner will run to a feature (maybe incorrectly mapped) using the printed map but the virtual control will have been placed accurately there using the Quickstart-like function in the Console. We have stock of old non-urban maps that were drawn before the days of LIDAR where placing features such as depressions and distinct trees was done to some extent by estimation. Using control features like these and the difficulties caused by tree canopy therefore make use of these old, non urban maps for MapRuns unsuitable. We have just used MapRun for Urban events/activities. Updating old maps for MapRun purposes is expensive and time consuming and requires much skill and knowledge. The KLM enables you then to publish the event either informally (Checksites) or formally through a Moderator. PXACV code enables me to trace my current position as I go around my MapRun Course (Checksites) and either check the control sites for accuracy of whilst competing in a small scale activity. One difficulty with this is where there is a location (depression/distinct tree/path junction etc) under a tree canopy. On the satellite view it is impossible to be accurate placing a virtual control under a tree canopy, or even a small depression out in the open...but the red dot created on PXACV does show my current gps location. Is there any way whilst out checking control sites using Checksite, for me to fix an added control to a course at my "Current Location" when at one of these difficult types of control sites..say, under a tree canopy, between two controls on a previously designed course I am walking...or even to simply walk around all the controls you might want to use on an event and to add these controls to the course as you go? GPS limitations excepted and presumably on a tablet with gps. If this can be done then MapRuns in non urban terrain on older maps could be possible - or I might be just talking rubbish. Let me know. |
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Paul
What you say about placing controls directly on the satellite imagery is correct. The "Create KML Course" is a simplified tool similar to Google Earth, which previously was the recommended tool. We always favour, if possible, to place controls on features you can see in satellite imagery, as the best way to get accurate Lat/Lng of controls. You may get away with placing controls based on an Orienteering Map, depending on the accuracy of the map, but remember moving a control just 1mm on a 1:10000 map, moves it 10m on the ground! (There is more discussion on this on the website). As you say, the accuracy of the map plays NO part in MapRun's punching. The only point to note, is that the display of controls (and tracks) in the MapRun App will show with the orienteering map (KMZ) as the background. Therefore controls and tracks can be confusing if the map is significantly off. If you can live with this, then simply creating a matching event in PPEN with controls shown in the correct relativity to features on the Orienteering Map gives the runners a good map to run with. (Of course when they look at their track it may look a little offset). MapRun can be used to accurately determine control locations, by visiting the site. Whilst displaying your location/track, you can tap the button in the top right to place a pin (with a label) at that location. When you export your track, these pins are included in the GPX file. Some mappers use MapRun (with this feature of dropping pins) to do site survey's for their mapping. However, the point to note is that it is best to use a good quality GPS unit that connects to your phone via bluetooth, if you want to get accurate locations... particularly under tree-cover. You can do a quick test with your phone, by visiting a particular site a few times and seeing what spread of results you get. Another way to get accurate locations is from the LIDAR data. The bottom line is that many clubs use MapRun for non-urban events. In summary: - if you can get the legs you want using control sites that you can see in satellite imagery, all the better, as a site visit is not required to get an accurate Lat/Lng (and Orienteering is about the legs, not the specific control locations and you may be able to get as good a leg with more GPS-friendly control sites... but not always.) - if you have LIDAR, or can get a good GPS reading in the field, then that will also work - if you have controls under thick vegetation, where the GPS accuracy will be inherently degraded, then you may consider increasing the punching tolerance in MapRun to greater than the default 15m to allow for greater noise in the location readings (and potential inaccuracy in the control Lat/Lng). Please reply if this doesn't address the points you raised. Peter |
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