Curious about GoogleMaps location accuracy

  • roland88

    roland88 - 2008-12-17

    I am wondering what others are doing with GoogleMap data when entering locations.

    For example, if someone lived, died and was buried in Sydney, do some of us pinpoint the locations and enter these as map data with GoogleMaps with exact locations, or do we just say Sydney for all?

    With the satellite overlays we can get right on top of the houses that link to events, so I guess we could all go a little crazy - haven't found the code for "lost virginity" here yet - but I can give you the GPS co-ordinates :)

    • Borksoft

      Borksoft - 2008-12-17

      Usually I just use the standard locations. In special situations I add the coordinates or add a new sub-location, for example a cemetery or a hospital. I don't expect people to zoom into the locations.
      Next to this, when you have a number of locations in one town and then some other in a town at a distance you will not be able to see the difference between the separate locations anymore, unless you zoom into one of the towns. If you just use one location in a town the different events will show up as tabs on the googlemap pinpoint when you click on it.

    • Anonymous - 2008-12-17

      For me its a matter of time and effort. I go to the lowest possible level I have the time and inclination to investigate. So an individual house when I have the time, but a city (or even country) when I don't, or if its a person who is perhaps quite a remote  link on my tree.

    • Paul Blair

      Paul Blair - 2008-12-17

      An interesting question.

      I rarely know the exact location (unless it's been given me as I don't search for them) so I try to point at the GM "label" - eg Sydney is Sydney, that is, I generalise.  But GM scaling can be a bit ratty, so at one scale the pointer is correct, at another it isn't. Kiwi and I have had this debate....


    • roland88

      roland88 - 2008-12-18

      Interesting comments - thanks. In the world of genealogy research we are often presented with quite vagueries - I find some kudos in finding an exact house from an 19th century census.

      Of course it matters not to someone who has no interest in that particular person, so it would be more of self satisfaction to go to such pin point accuracies.

      One thing I have learnt is that each of our historic paths is unique, hence the need to one's own research since no one would have researched your unique path.

      Also it is quite sad to see people accept other people's research so readily without checking. is a classic, I accidently copied up some incorrect data, after I discovered it I checked around and it was already listed as a "OneTree" fact.

  • knorway

    knorway - 2009-10-24

    While this is almost a year after the discussion, I'm rather new to PGV, however I have been doing genealogy myself for 10 years and extending work of others started 70 years ago.   In some cases I have exact locations for houses, graves and other "important" happenings.  I have been recording much of this info over the years as part of the PLACe location because other individuals may be interested in knowing/finding the spot (I am).  I hope to use GM to help people virtually go to a location that they may never physically go to.

    One problem (probably the ratty issue Paul talks about) I have is that in some cases GoogleMaps does not seem to honor the zoom when drilling down in the Place Hierarchy or centers the page to include lower points that are right now not material to the display.

    Before PGV (and the GM module) I used GM and other mapping software to capture locations and create my own maps to develop my virtual tour of the location things that occurred in history.

    Just some points of interest for me.  Thanks

  • Paul Blair

    Paul Blair - 2009-10-24

    You can improve accuracy for yourself. I tend to go ito GM configuration, and set the 'precision' for places a point or two higher than the default. Then I get the co-ords to that level of accuracy, enter them, then adjust the zoom factor to suit. For example, a country would be 4, a building would be 10 or 11. That means that you have got the place accurately, even if the GM display (at the initial opening of the map) seems a bit innacurate. Drilling down will show you an accurate representation.


  • knorway

    knorway - 2009-10-24

    Ok, I'll review my zooms.   And play around a little.  Thanks for the encouragement.

  • Anonymous - 2009-10-24

    The entire question of the accuracy of any mapping software is a very complex issue. Here's just one example of thousands of discussions about it on the web:

    Even comparing google maps with google eartth will get you different results. There's really not much PGV can do about that.

  • knorway

    knorway - 2009-10-24

    A very interesting article!  I guess the next time I'm out at a grave site I'll get my GPS out and record the exact location for my files.  Just kidding :-)

  • Paul Blair

    Paul Blair - 2009-11-04

    Um….not so strange!

    A couple of years ago, I began to 'map' cemetery locations in Australia. Along the way, I met various people who offered advice. One gent I met this way does exactly what you say - his interred rellies are all geolocations to him!  :-)


  • Laie Techie

    Laie Techie - 2009-11-19

    If I take photos with my iPhone, it stores GPS information. Granted, iPhone doesn't have the best resolution (and no way to zoom!) and the coordinates are triangulated for the earlier models (iPhone 3Gs added a GPS chip), but it's useful all the same. Perhaps I should take 1 photo with my iPhone to capture the GPS, then use a real camera for the actual photos I'm going to keep…

  • Greg Roach

    Greg Roach - 2009-11-19

    I don't know what sort of "real" camera you have, but mine (Nikon DSLR)  lets you plug in a GPS unit (google Nikon GP-1), and the co-ords get added to the image's EXIF data.

  • Paul McGrath

    Paul McGrath - 2009-11-20

    I have an issue with the 'actual' accuracy of the google map locations, whether it is a google maps issue or a PGV one.  When I pinpoint a place and then go back to it the pointer is off slightly.

    Does anyone else have this problem?

  • Łukasz Wileński

    In the google map module config you have the "accuracy config". I think you should change this to more digits after decimal

  • Paul McGrath

    Paul McGrath - 2009-11-20

    thank you I will


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