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When I add aerial images from a recent survey (delivered in EPSG:31468, DHDN_3_Degree_Gauss_Zone_4) to an empty project together with an OpenLayers OSM layer I'm facing a strange positioning issue. I carried out the following steps:

  • Set up a new project with 'on the fly' projection enabled and project SRS set to EPSG:31468
  • add the aerial image
  • add OpenLayers plugin OpenStreetMap layer

The layers positions fit somewhere in the left part of the canvas (screenshots below, green) but dragging the map canvas a few hundred meters causes positioning gaps of the same area (screenshots below, red):

Correct position left of the map canvas:

enter image description here

Dragging 300m N:

enter image description here

Dragging 800m E:

enter image description here

According to the comment to ArcGIS for Desktop 10.4 - aerial images not in correct postion I tried to set up a transformation as shown below, but this seems to have no effect. What might be the reason for this behaviour?

Transformatino settings

enter image description here

Community
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Jochen Schwarze
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    Does the same issue occur if you instead use the QuickMapServices plugin? – Joseph Jul 04 '16 at 10:24
  • Nope, QuickMapServices plugin works pretty well. On the other hand, OpenLayers Plugin works pretty well too, when only selecting EPSG:3857 (WGS 84 - Pseudo Mercator) as the projects srs... – Jochen Schwarze Jul 04 '16 at 11:15
  • I noticed there has been a recent update to the OpenLayers plugin too but the choice is yours as to which one you want to use :) – Joseph Jul 04 '16 at 11:19

1 Answers1

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The Openlayers plugin has always had trouble when the project CRS is not EPSG:3857. QuickmapServices should overcome this.

If you want to stick to OL, set the project CRS as needed, and reproject your DHDN layer to EPSG:3857, on-the-fly or permanently.

Note that EPSG:3857 is not useful if you need to measure lengths or areas.

AndreJ
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