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I am in need of fine resolution elevation data from which I can extract slope and aspect for Oxfordshire county in England. I have found that the UK's Department for Environment Food & Rural Affairs data portal freely provides 1m resolution Digital Surface Model (DSF) for the UK, including already extracted slope and aspect products, hyperlinked.

I easily accessed the DSF as a WMS and was also able to view the slope and aspect products as ArcGIS Map Services, both is QGIS. Since these are only images, I want to the actual slope and aspect raster products to continue with my analyses. Hence, I am trying to convert these to rasters. I clicked on the links for the slope, aspect and DSM products in the above link, to get what format of data I can extract i.e. TIFF etc and I do not think there is any such info provided i.e. the metadata does not provide info on what is the raw data.

As per this post, I tried to export the slope and aspect data out as a GeoTIFF, which results in the error- enter image description here. I then tried converting to .vrt using the Raster> Miscellaneous>Build Virtual Raster and then work with .vrt, which firstly I could not open in QGIS let alone export out as a GeoTIFF.

How can I proceed to extract the slope and aspect data from this 1m resolution DSM product provided freely from the UK government?

Vince
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tg110
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    The WMS doesn't give you the data just A tinted shaded relief, which is an image showing what LIDAR looks like when loaded into specialist software. To get the data you'll need to use one of the Image Service endpoints – nmtoken May 05 '23 at 13:15
  • @nmtoken- the aspect and slope products on the page I have linked are Image Service endpoints – tg110 May 05 '23 at 13:22
  • An Image service is an ESRI defined interface, it is not a WMS which is what the question as titled/tagged is asking about. You man want to try using https://plugins.qgis.org/plugins/ImageServerConnector/ – nmtoken May 05 '23 at 14:10
  • At the bottom there is the option to Export Image https://environment.data.gov.uk/image/rest/services/SURVEY/LIDAR_Composite_1m_Last_Return_DSM_2022_Aspect/ImageServer – Mapperz May 05 '23 at 14:19
  • The EA/Defra DSM/DTM WMS endpoint URLs and the data download links are constantly down and/or changing from my experience. For example, the data download site throws an error: https://environment.data.gov.uk/survey and loading the WMS into QGIS tends to timesout. (as of Jan 24). – Theo F Jan 03 '24 at 14:56

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