Topography in google earth pro5/9/2024 You can also view the first edition maps, and ozultimate has created a nice interface allowing you to fade between the two. There you can configure one of the base maps to be the current topo maps, as well as overlay important information such as ‘lot boundaries’ which can be useful when exploring areas near private property. Online you can view the NSW topo maps via different interfaces. The ‘network links’ to the SIX Maps servers I had made were still working but these had always been unreliable and cantankerous. Whilst the satellite imagery is nice to use, having a topographic basemap is also indispensable. ![]() All the names I saw looked familiar but to took me a while to start linking all the places back together in my head. I dug up my old Google Earth files and loaded them up. Last edited by RHaslam on April 29th, 2017, 9:40 pm, edited 1 time in total.Being locked up in hotel quarantine for two weeks gave me a decent amount of time to re-familiarise myself with the local Australian bush using maps. Here's a blow up that shows the discrepancies better. Sometimes I think it was better to navigate when some things were still a mystery, because the technologies creates its own mysteries. Could be from the rivers moving, or perhaps inaccurate transcribings in the first place.įor instance, this track of the Onamon river was done with basecamp set to nad27 and my GPS set to Nad 27. They take up an entire four tier filing cabinet, as well as four other boxes.Īs Nessmuk stated, there are quite a few discrepancies for river travel, even if your GPS is plugged into the correct datun field. I still have the entire set of aerial photographs of Ontario, used to construct the maps, along with the stereoscopic eye piece to view them. Just as a point of interest, most of those Nad 27 maps are from aerial photos from around 1927. It's one of those things that a lot of people don't realize. There is quite a discrepancy between WGS 84 and Nad 27, which has caused some folks problems when I send them maps. ![]() Most on the topos I use are Nad27, so I leave basecamp in Nad 27 as well. I was able to interface it with my basecamp program, where you can choose the datum field that is best. This particular topo map dates from surveys taken way back in 1962. I have seen signficant changes in the river ( and GE images) in the course of a single year. Many of the islands, shoals, cutoffs change almost every year. However, when the Nad27 topo map is overlain, there is a dramatic shift in the route and waypoints, since they are WGS-84 but the map is not.Īnother issue I would have is this river ( and I assume other similar far northern Canadian rivers) are not static. I know from being there 4 times that registration of my route and waypoints using the GE mapped waypoints is accurate with reality. ![]() Here is a segment of my Yukon River race route map with waypoints (labeled in tenths of a mile beginning from Whitehorse). So you will get a position shift if you overlay the topo on GE. But the topo maps are referenced to NAD27 datum. How do you account for the differences in datum? Google Earth is set to WGS-84 datum ( not changeable as far as I know). In Google Earth choose File - Open - Navigate to the downloaded file. It is also what makes it difficult to stitch multiple maps togetherģ. The Collar is the border around a map with the legend, title, declination etc. The other problem with CanMatrix Maps is you can not get them Collarless. Canmatrix maps are my favourite because they have the most detail that paddlers might find useful. Cantopo is the newest, but has the least amount content for paddlers. Canada offers Toporama Maps, CanTopo Maps, CanMatrix Maps (probably others too). What is an index? It is essentially a grid of Canada. There may be others but these are the ones I find most useful. These index files include Toporama collarless map index, CanTopo Collarless index, CanMatrix 50k index and CanMatrix 250k index. ![]() The Government of Canada has made KML/KMZ index files for use in Google Earth (a KML/KMZ file is a file that Google Earth can open). Get the Canadian Map indexes for Google Earth
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