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I have a set of data that I created from gps locations of images. The locations are in decimal. I don't know what projection was used when the data was captured. I used QGIS to display the data with a forced projection (EPSG:28355 - GDA94 / MGA zone 55) but the data looks wrong. The resulting map is off by nearly 90 degrees and the circular streets are skewed. So I am assuming that the projection is wrong and I can't work out how to change it. Can someone help?

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Please search our site for solutions. If they don't help, you will need to supply more detailed information: "off" and "skewed" are merely suggestive, whereas quantitative information about the errors can help solve the problem. – whuber May 23 '13 at 22:25
You could try entering an XY into ProjFinder and see if anything hits. – RyanDalton May 23 '13 at 22:55
@RyanDalton - thank you for the terrific site, but it didn't help me. – Johanna May 23 '13 at 23:40
OK, to be more quantitative about my problem. The data I have represents points along the road network in my city. The layout of the main arterial streets is east west. My data points should line up with this east west alignment. But my points are in a NNE / SSW alignment. We also have circular streets. My data shows these as eliptical. – Johanna May 23 '13 at 23:43
GPS should have captured the coordinates in wgs 84 geographicals. Have you re-projected the data from decimal degrees to GDA94 / MGA zone 55 or is the software projecting the data on the fly?? Actually what did you mean gps locations of images (eg screen capture of Google Earcth showing the GPS points) – TsvGis May 24 '13 at 1:16

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