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Author Topic: Massive error in dimensions after export to AutoCAD?  (Read 1711 times)

philnesterovic

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Massive error in dimensions after export to AutoCAD?
« on: January 03, 2016, 07:22:20 PM »
Hi all!

I'm fairly new to Photoscan and absolutely love what the product is doing to me. I'm having a minor problem though.

I've been manually inserting markers on my model, then exporting the long/lat/alt of the markers to a .txt, then importing into AutoCAD 2013. When I look at the distance between key points on Photoscan using scale bars, the distances are dead on. However, when I check the dimensions of the design in AutoCAD, they are way off- namely are extremely small numbers (20 m becomes 0.000001 m). The points are proportionately correct, so I do have the option to just scale it in AutoCAD, but this is not an ideal workaround.

Does anybody have an explanation for this? I find scaling it introduced unnecessary error into the model.

Thanks!

James

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Re: Massive error in dimensions after export to AutoCAD?
« Reply #1 on: January 03, 2016, 08:33:09 PM »
Just a guess, probably photoscan understands that your coordinates are degrees north and east, (lat and long) whereas AutoCAD treats them as Cartesian coordinates in x,y,z and assumes whatever units you have AutoCAD set to import in. Either convert the photoscan project to local coordinates, or somehow inform AutoCAD that these are lat and long angular units.