Raster Reference Origin. Why is it where it is?

OK this has bother me for quite awhile so I need to ask.

If you attach a raster reference the default location places with the upper left corner of the image at 0,0.

If you attach interactive it uses 2 opposite corners via data points.

The question is why is the origin of the file the UPPER left corner of the the BOTTOM left pixel?  Why not at the corner of the image? 

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  • Hi David,

    I wonder why this behavior bothers you, since usually it is probably more convenient to place a raster with no geo-reference interactively anyway, no?

    Thanks,

    Mathieu



  • Mine get place by the at UPPER left conner of the Lower left pixel.  It bother me because the origin is not the placement point.  When I scale an image it doesn't scale about the lower left or the upper right.  It scales about the UPPER RIGHT corner of the LOWER LEFT pixel.  Its really a strange place to establish an origin.

    Edit,  Ok I did some more experimenting.  I was wrong it is not scaling about the point I mentioned, only appeared that way.  It is placed Upper Left and scales about Lower Left as Inga  stated.  It just happens that the scale factor I use (because of the latitude I'm at) is almost exactly the distance between lower left corner and upper on placement.   When I scale the image via pixel size 0,0 falls very very close to the upper left corner of the lower left pixel as the image shows.

    My apologies for the confusion.

    Regards,

    DavidG

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  • Mine get place by the at UPPER left conner of the Lower left pixel.  It bother me because the origin is not the placement point.  When I scale an image it doesn't scale about the lower left or the upper right.  It scales about the UPPER RIGHT corner of the LOWER LEFT pixel.  Its really a strange place to establish an origin.

    Edit,  Ok I did some more experimenting.  I was wrong it is not scaling about the point I mentioned, only appeared that way.  It is placed Upper Left and scales about Lower Left as Inga  stated.  It just happens that the scale factor I use (because of the latitude I'm at) is almost exactly the distance between lower left corner and upper on placement.   When I scale the image via pixel size 0,0 falls very very close to the upper left corner of the lower left pixel as the image shows.

    My apologies for the confusion.

    Regards,

    DavidG

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