We support the most popular local coordinate systems for all of our imagery. Depending on which coordinate system your GIS application is configured with, you can request imagery in the following coordinate systems:

• Australia - GDA94 and GDA2020
• USA - NAD83
• Canada - NAD83CSRS
• New Zealand - NZGD2000 

When requesting imagery using WGS84 coordinate systems, namely EPSG:4326 (WGS 84) and EPSG:3857 (Web Mercator, Spherical Mercator, Pseudo-Mercator), our WMS service will automatically return imagery that has been converted to a local coordinate system as shown in the table below.

Assumed datum - for Australian customers

Several web applications assume GDA94 where the datum is not specified. You can see from the table above that in Australia, Nearmap WMS 2.0 defaults to GDA2020.

We provide a way to force the returned imagery to GDA94 with a custom request parameter  DATUM . The behaviour of this parameter depends on the projection the imagery is requested in (SRS Parameter), as shown in the table below.

Advantages of assumed datum

If your application relies on assumed GDA94, the alignment and accuracy can be improved by a significant margin, as you can see in the images below.

Default behaviour

With GDA94 override

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FAQ

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  What are the best practices for defining areas? —

  Use simple boundaries around your areas of interest. The imagery is not requested until you interact with the application, so there is little difference in what imagery is returned when the custom service is used.

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  Should I use Simple or Custom WMS? —

  The simple WMS should be used if you want the only latest imagery for your area (Australia/New Zealand/USA/Canada). You will not be able to perform geofencing or navigate time. Custom WMS will allow you to perform geofencing and to set up specified regions as the only imagery you can view. For those regions, you will be able to navigate the time and set boundaries for the dates.

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  Can we limit the date range when creating the custom polygon? —

  Yes, the custom WMS allows you to limit the date range. You can specify either start date or end date, or both. It limits the surveys you get back as layers in your service. 

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  Can I specify a polygon programmatically? —

  No, you cannot create a polygon programmatically. 

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  If we create many areas, does it have a performance impact? —

  The performance impact is not so much dependent on the size of the area, but on the number of surveys you bring back. There is a limit on how big an individual area can be, currently set at about 5000 km², and you can specify up to ten areas in the same service. If you bring in ten metropolitan areas around Australia, you could be loading thousands of surveys. That would slow down your initial loading into your GIS application.

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  Are there limits to the Custom WMS services? —

  • Maximum number of WMS places - 50
  • Maximum number of areas per place - 10
  • Maximum area size - 15,000 km²
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  When loading into QGIS without the satellite imagery, why wasn't I able to remove the black around the aerial imagery? —

  This is probably because your layer is brought through QGIS by default with JPEG. JPEG does not have transparency support, so when there are areas with no data, they are displayed as black. We recommend that if you want to look at a zoomed out version of Nearmap imagery, for example when you're looking at a whole city or state, bring it in as PNG. If you're working mainly with zoomed in imagery, bring it in as JPEG. 

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  Can I upload a KML/Shapefile/FileGeoDatabase to define my areas to limit usage to precisely my areas? —

  No, you need to draw your areas, and the usage is only incurred at the time of browsing imagery in your GIS application.

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  Is WMS 2.0 more accurate than what I am currently using? —

  Australia - We have adjusted the datum of the imagery that is returned by default when you don’t specify a projection, i.e. rely on application defaults. WMS 2.0 will automatically adjust the imagery to GDA2020 coordinate system for Australia and NZGD2000 for New Zealand. This will reduce positional errors and projection mismatches ensuring your imagery lines up. WMS 2.0 will continue to support the GDA94 MGA zone projections in Australia.

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  What do you see if you constrict start and end dates? —

  When you constrain a start date, to exclude older imagery, for an area if no more recent imagery is available, is a blank layer returned or your default, low-res (old) satellite imagery?  It would be very useful to see that there is no recent imagery after the constrained end date.

  You simply get no layers if you create an area with a polygon and restrict the dates to a particular range. The satellite layer, which was by default included in our last version of WMS, is no longer included in the responses, so you do not get satellite imagery unless you explicitly ask for it. So yes, it would be possible to see that there is no recent imagery after the constrained end date. 

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  How do I use GDA2020 projections? —

  For Simple WMS all AU MGA zones are available in both GDA94 and GDA2020. For Custom WMS only the zones that intersect with the area of interest will be available as an option to request imagery in.

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  How do I use State Plane projections? —

  Only available in Custom WMS. Only the state plane projections that intersect with the area of interest will be available as an option to request imagery in.

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  When selecting an area can I select our local government boundary? —

  Yes, you can select any area, and it doesn't have to be exact. You will need to draw the area though, you cannot import your boundaries.

  When you create an area in the self-service API portal, you're defining a template/metadata for that particular service, at that point no data is downloaded. We recommend that when you are interested in an area you roughly sketch out around that area, it doesn't matter if it is not following your local government area boundaries. The data is only downloaded when you bring it into the application, and you start interacting with the imagery in the application. 

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  Is there a way to know what is the date of the latest imagery? —

  Yes, in custom WMS you can know the date of the latest imagery, while in simple WMS you cannot. When you bring in the in the custom WMS the date layers are synced up to the latest imagery, and you know exactly which dates you are bringing in. With simple WMS there is no way to get at the dates, since it is a very simple lightweight service.

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  Does interacting with the imagery in the area definition window count towards my usage? —

  Yes. When you define an area, a small amount of imagery is loaded to provide context for where we have coverage. We envisage that there will be very little usage coming from this tool because:

  • The map is very small, i.e. not full screen
  • It is used infrequently to create services