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I have the following set of points (there are far more). Originally they were given to me without any decimals. I was able to correctly plot them into arcmap however they don't line up with my other shapes, they float off to no where. I've tried re projecting and define projection, but they still go no where. I can only conclude they are incorrect co-ordinates, as when I try to google maps a point (-33.726298, 127.575079) google maps can't find it.

Points in the area I am looking at should look like -37.837266, 145.040987. I cannot understand how I was able to create shapes from these points that look correct, but don't line up with my layers, other than the distance between each point is still correct. They are meant to be in GDA94, but I still can't locate them in the Melbourne area where they should be.

 x               y
3372629.81  1275750.79
3370659.42  1276207.50
3370415.87  1275014.01
3368757.31  1275354.90
3368493.70  1274241.98
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  • What projected coordinate system did you define for these points? And, just as importantly what were the precise steps that you performed to try and get them displayed in ArcMap? The points themselves both have 7 digits and I am wondering whether they are Lamberts or Albers, rather than from an MGA Zone.
    – PolyGeo
    Commented Nov 25, 2015 at 5:01
  • Sylvia, if you could ask your data provider where they get their data (govt site?) or if they know anything more about this coordinate reference system, I'd like to get it added to the EPSG registry so that it's easier to find in the future!
    – mkennedy
    Commented Nov 25, 2015 at 18:21
  • they created their data in microstation. I am not sure if this is standard for CAD users to use this projection.
    – Sylvia N
    Commented Nov 25, 2015 at 23:47

1 Answer 1

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I think I've found it. The definition is unknown to Esri and to EPSG. I found a reference to a "BEST" VicGrid coordinate reference system described by Simon Greener.

When I defined it in ArcMap, I got coordinate values similar to the OP's.

The definition is:

GeoCRS: GDA 1994
Projection: Lambert conformal conic
Units: Metres
Latitude of origin/center: -27.0 
Central meridian/longitude of center: 135.0 
Standard parallel 1: -18.0
Standard parallel 2: -36.0
falseEasting: 2500000.0
falseNorthing: 2500000.0
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  • you are right, I received an email from the provider saying they were in GDA94. But when I projected it to GDA94 it was stlil floating in space, which I see now the Arcmap GDA94 is different from the one you have above. How were you able to define it if its not available in arcmap? – I see you can add a new co-ordinate system..
    – Sylvia N
    Commented Nov 25, 2015 at 22:34
  • So I was able to define it using the co-ordinate system you pasted above, but I am still unable to make it line up with my other layers even when I project it to the standard vicgrid.
    – Sylvia N
    Commented Nov 25, 2015 at 22:43
  • How far is it off?
    – mkennedy
    Commented Nov 25, 2015 at 23:16
  • it doesn't appear to be near anything. I could ask the supplier to send the points again in a standard projection however I had already created 80 polygons from the points.
    – Sylvia N
    Commented Nov 25, 2015 at 23:35
  • Hmmm, if you want to send me the data, or a poly/point out of it, I can take a look at it: my user name at esri dot com. I will faithfully delete as soon as I'm done. However, I'm only here until 1700 PST until next Monday (thanksgiving holidays in the US). I'll need to know where should be--street intersection, something.
    – mkennedy
    Commented Nov 25, 2015 at 23:42

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