Free LIDAR data for England

Brains

Brains

Well-known member
Not being overly GIS savvy I didnt try to open the data, so dont know how! Perhaps via Minecraft?  :-[
 
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Peter Burgess

New member
Brains said:
Not being overly GIS savvy I didnt try to open the data, so dont know how! Perhaps via Minecraft?  :-[
Click to expand...
Looks to me like you need AutoCAD, and you also need to know how to use it.

https://forums.autodesk.com/t5/autocad-map-3d-general/importing-lidar-data-in-the-form-of-a-asc-file/td-p/5741840
 
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peterk

Member
I haven't studied this document https://www.swaag.org/LIDAR/LIDAR%20Image%20Processing%20for%20Amateur%20Archaeology%20Groups.pdf
Summary: This short article describes how free software and LIDAR images can be processed to
show earthwork features at their best by varying the angle a ?Virtual Sun? is casting its shadows.

It references LIDAR data from http://www.geomatics-group.co.uk/ and since when that site is down it says " If you require LIDAR Open Data, go to. http://environment.data.gov.uk/ds/survey#/" I think the data is identical and the instructions are common.
 
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RichardB1983

Member
First post! Hope this is ok. I've just tried downloading some data for Ingleborough and putting it through some free GIS software - and applying the "virtual Sun" as described. It's set for roughly the same lighting conditions for midday on mid-Winter's day.

I've put two images together. The first is a large-scale area showing the edge of Simon Fell on the left and Alum Pot at the top.


The 2nd is a close-up view of the main path up from Horton to Ingleborough summit as it climbs through the limestone pavements. You can see some quite small features.
Close-up:


Both use the EA 1m resolution LIDAR data. Unfortunately most outdoor areas don't have any coverage yet, but I think there may be an additional data release at some point.
 
bograt

bograt

Active member
I would find this really useful for a few projects I'm helping out with, managed to download some LIDAR files, now looking for the app to open them with, where did you find the 'free GIS software' Richard, the files are in .ASC format.
 
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Fulk

Well-known member
There?s something really odd about these images ? well, to my eyes, at any rate.

In the top one I get the distinct impression that what should be hollows are protuberances, and vice versa, so to me the stream channels look a bit like veins standing out from skin, and the shakeholes look like pimples.

However, I dragged the image to my desktop and turned it round (so that Simon?s Fell is to the top, Alum Pot lower down) and now the channels look like channels and the shakeholes like depressions.

Does anyone else see it like this?
 
HardenClimber3

HardenClimber3

Member
How strange....
Presumably it's something to do with where we assume the sun is?
(and it also looks okay if you only rotate it 90o  l or r.
 
Simon Wilson

Simon Wilson

New member
HardenClimber3 said:
How strange....
Presumably it's something to do with where we assume the sun is?
(and it also looks okay if you only rotate it 90o  l or r.
Click to expand...

It's because you expect things to be illuminated from above.
 
R

RichardB1983

Member
Wayland Smith said:
THIS  http://gis.stackexchange.com/questions/61416/how-do-i-import-uk-environment-agency-lidar-data-asc-into-quantum-gis

May be an answer (for free)
Click to expand...

Yes. I used QGIS. The EA tiles open as a raster layer, and there are a few "terrain analysis" tools available. The images I posted were from "Hillshade" option, which allows you to select a lighting angle for your virtual Sun. If you don't like the virtual Sun angle, you can change it easily. I chose quite a low Sun angle on these images, as it normally creates a larger contrast between areas that vary in altitude. It's easier to look at craters on the Moon when they're near the edge of the illuminated portion of the Moon as the shadows are longer.

The "Slope" option looks very interesting for that part of the Dales - i.e. it higlights changes in gradient - which shows up most of the shakeholes quite well, but there are some interesting features of the general landscape you can see with that plot too.
 
bograt

bograt

Active member
Thanks Wayland & RichardB, have located and downloaded the QGIS software, now can't find the original .ASC downloads  :cry: :cry: - AARGHH--
( I guess I'm just a drunken, senile old sod ---)

Off to the LIDAR site again to download and have a play.  (y)
 
2xw

2xw

Active member
This data is a great release. From a caving and hydrological modelling point of view however many regions you might want is not covered. For example, stoney middleton and bradwell moor are only covered by 2m resolution which is great but not amazing. Sheffield city centre is at a 25cm resolution which I wish was the case for the caves.
I have Arcgis etc if anyone wants any images or whatever I'll do my best to download and send, drop me a pm
 
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