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Queensland Globe – Nearly Nearmap

Earth from space

Queensland Globe free spatial data

We’ve taken the loss of Nearmap hard but now here in Queensland is something pretty close. I have to say I’m very relieved.

Queensland Globe (QG) is a Queensland Government open data initiative which uses Google Earth (GE) to present a variety of spatial data and they are progressively adding more.

[button link=”http://www.nrm.qld.gov.au/mapping/queensland-globe.html” style=”info” color=”orange” window=”yes”]Learn more of QLD Globe[/button]

Queensland Globe Pro

You will want to use qglobepro instead of regular qglobe, but it’s hidden away. Download the .kml file, open it and GE will start up with checkboxes for QG data in the Layers pane on the left.

[button link=”http://globe.information.qld.gov.au/GoogleInstall/qldglobepro.kml” style=”download” color=”aqua” window=”yes”]QLD Globe Pro kml[/button]

Remember you need to switch off terrain features or you will have a parallax view which is no use for mapping:

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  1. In GE: Tools / Options / 3D View / Elevation Exaggeration = 0.01.
  2. In the QG checkboxes: Terrain = Off.

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Queensland Globe screen
Queensland Globe screen

Here is why Queensland Globe is special

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  • The aerial photography is reasonably up to date in the areas I have looked; it’s not as good as Nearmap, but a lot better than Google Maps (GM).
  • The aerial photography has been selected for clarity, unlike GM, which can be murky, shadowed and useless.
  • The orthorectification of the aerial photography appears to be quite accurate.
  • Photography is high definition – again better than GM but not as good as Nearmap.
  • It has 10m contours which look reasonably good.

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But Queensland Globe is not perfect:

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  • No georeferencing information is available, but see below.
  • Contours disappear when you zoom in very close.
  • Cadastre is unreliable and sometimes appears only when zoomed out too far for usefulness. Just keep trying.
  • Images can’t be downloaded, you have to take screenshots.

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Georeferencing

Here is how to add georeferencing information to the GE / GQ image. Download the Gridlines Manager .kml file.

[button link=”http://nearby.org.uk/google/Gridlines_mgrs.kml.pl” style=”download” color=”aqua” window=”yes”]Gridlines Manager kml[/button]

This one appears in the Place pane in GE (I’m not sure how or why) and will remain there for future use. (It seems to be necessary to load the QG KML file each time.) Switch on 0.1km grid lines as well as the QG imagery and contours, take a screenshot and you have an image which you can easily load into Ocad and print out for fieldworking.

Once again the gridlines are not entirely reliable, sometimes they don’t display, I think because the system relies upon the availability of a server somewhere to provide the data.

How to load the image in Ocad? I find it’s easiest to import a GPX track somewhere in the vicinity of your map, as this fixes up your map’s Coordinate System, Zone and Offset, and locates you near where you want to be. Now in Ocad go to Map | Set Scale etc and set a grid distance of 100m. Switch on the grid and you can now load the QG image and adjust to the gridlines.

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VIC, NSW, NZ Release Free Spatial Data

data.vic home page extract

Recent releases

July saw Victoria follow NSW in making available online, free spatial data free. New Zealand’s LINZ released a significant amount of aerial imagery with more to follow. I checked out the VIC release and created a quick guide for those not familiar with accessing spatial data.

Apart from being useful to create base maps, spatial data makes it easy to georeference existing maps. The most useful data sets for orienteering and rogaining are elevation (contours, spot heights), transport (road, rail, tracks), hydro (lakes, streams, watercourses), property boundaries and vegetation density. Most of those data sets have associated infrastructure but some might be obtained from a features data set.

The remainder of this post deals with my quick survey of the VIC offering. The situation is likely to be broadly similar in other states.

Victoria

900 data sets released on data.vic.gov.au

While Orienteering Victoria has had a free data licence for some years, acquiring a data set cost $200 for the work involved. Not to mention the time of orienteers in preparing and submitting the application.

Now you can download seemingly any or all of the six data sets useful to map sports to some degree.

Rail data on map
Preview of rail data overlaid on map

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  • Elevation
  • hydro
  • transport
  • vegetation
  • features
  • property.

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Another 100 data sets will be available by September.

Locating your data sets

Easiest is to download the Guide below and search using the ID attached to each recommended data set. If you wish to peruse at leisure then read on.

Each data set may appear in multiple categories. For sport purposes, it appears easiest to search for or select a data set name that includes the words VicMap 1:25,000. These data sets include subsets that otherwise you would need to locate and order individually. For example, Vicmap Hydro 1:25,000 includes subsets watercourses (rivers, streams, channels…), water points (ponds, dams…), water areas (lakes, reservoirs…).

However, the listings are not perfect. For example at time of writing, the Spatial | Transport section does not include VicMap Transport 1:25,000 but does include VicMap Vegetation 1:25,000 (I have notified this).

A quick guide

For the uninitiated, selection of an appropriate data set may seem daunting when you first hit data.vic.gov.au. For example, if you select Transport from the category list shown you end up with social data sets, not spatial data sets. You first have to select Spatial, then the relevant sub category.

And which data format you select depends upon your edition of OCAD. For Professional, select ESRI Shape. For Standard, select Autocad DXF.

To assist, while watching the exciting Tour de France Mont Ventoux stage, I delved into the web site and prepared a quick guide which you can download. It will not be perfect but it should help you avoid long detours. I will update it as necessary (let me know of any errors) and am working on some short video guides.

[ilink url=”https://ocad.com.au/wp-content/uploads/2013/07/Kens-guide-to-free-Vic-spatial-data.pdf” style=”download”]Guide to access free VIC spatial data.[/ilink]    1 page pdf. Updated 17 July 2013.

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