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irfan7 post(s)
#03-Feb-21 10:32

hi,

I am creating polygon contour form STRM data (Geo tiff/WGS-84) in Manifold.

Within Manifold both polygon contour and grid are seamless.

But when I compare original grid with exported contour Shapefile in ArcGIS, there is big shift.

My guess is, I must change Projection properties. At the moment, I am taking default values (image attached).

Can somebody suggest which values should I use?

I am using Manifold 8.0.30.0 on Windows Server 2016

Thanks in advance.

Attachments:
grid projection.png

tjhb

9,627 post(s)
#03-Feb-21 18:30

After creating contours in Manifold, use Change Projection (not Assign Projection) to change both Local Offset values to 0 and both Local Scale values to 1.

Currently they have values inherited from the surface they were made from, which has advantages within Manifold, but those values are incompatible with other software.

The same needs to be done before exporting any data derived from images or surfaces in Manifold 8.

Manifold 9 handles it automatically (or should).

tjhb

9,627 post(s)
#04-Feb-21 02:32

Slight corrections on re-reading:

After creating contours in Manifold, use Change Projection (not Assign Projection) [for the contour drawing] to change both Local Offset values to 0 and both Local Scale values to 1.

...

The same needs to be done before exporting any data drawings derived from images or surfaces in Manifold 8. [Not with new images or surfaces, that would be bad.]

irfan7 post(s)
#04-Feb-21 13:59

thanks it works.

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