1
vote
1answer
53 views

Can I define a transformation between 2D and 3D in Geotools?

I'm using Geotools, and I need to convert coordinates between 2D and 3D coordinate reference systems. I recognize that there's no universally-correct way to do this: 2D -> 3D means "making up" a Z ...
0
votes
2answers
81 views

Defining a scale number from the Helmert transformation

I know this is more bit of a cartographic issue, but maybe somebody would be able to help. I have an old map georeferenced to the openstreetmap with 50 identical points. I want to get the scale of the ...
2
votes
0answers
60 views

Using ST_Affine() and trans_param() functions on vector layer

After reading this post How to georeference a vector layer with control points? I decided to give it a try to move/rotation/scale a polygon using Postgis. I have two polygons, polygon_from and ...
2
votes
1answer
173 views

QGIS Georeferencer, unexpected transformation, and GCP placement

Im trying to get the sample map which i believe to be EPSG:3112 into QGIS and geo referenced. In my screenshot, on the right is the raster in georeferencer with the points i have added. On the left is ...
2
votes
2answers
468 views

How to create a “Datum-less” projection in QGIS?

I want to use QGIS to do some georeferencing and image registration. On ArcMap10 I can define an "Unknown Projection", basically a default metric grid, and use it as a grid for georeferncing. In QGIS ...
3
votes
1answer
512 views

Transform multiple layers as one unit in ArcGIS 10?

The general/conceptual question: Is there a way to transform multiple layers together in ArcMap 10 (on Windows XP SP3) as one unit? More specifically: I have an ArcMap document with a georeferenced ...