SoA Forums

History => Ancient and Medieval History => Topic started by: Imperial Dave on January 02, 2017, 09:50:25 AM

Title: LiDAR mapping
Post by: Imperial Dave on January 02, 2017, 09:50:25 AM
My favourite waste of time is looking at satellite maps of Britain (in conjunction with trying to tie up historical sites). Recently I have been really interested in the revolution of LiDAR which although isnt that new, its potential usages are immense and we are only just scratching the surface of those uses. For those who dont know what it is, here are a couple of links

http://shornewoodsarchaeology.co.uk/lidar-what-is-it

http://www.archaeological-surveys.co.uk/lidar/

For those who are really interested, here are various links to survey sites

https://houseprices.io/lab/lidar/map
http://lle.gov.wales/home?lang=en
https://data.gov.uk/dataset/lidar-composite-dtm-2m1

very interesting stuff and hours of fun (a relative term ;) )
Title: Re: LiDAR mapping
Post by: Patrick Waterson on January 02, 2017, 12:06:10 PM
It could be particularly helpful in combination with magnetometry, provided of course everyone has a good idea of what to look for.  The whole field of remote sensing has promising archaeological applications, though we need some real archaeology correlated with 'before' and 'after' shots from the remote sensing apparatus to be certain of identifying features correctly.
Title: Re: LiDAR mapping
Post by: Imperial Dave on January 02, 2017, 12:31:59 PM
agreed Patrick.

Its funny that some of the features I know around my area dont actually show up that well on LiDAR but others really come to prominence. Overlayering different systems is the way to go for sure. I still reckon LiDAR is one of the best things I have seen in a long while
Title: Re: LiDAR mapping
Post by: Imperial Dave on January 15, 2017, 08:44:49 AM
latest example of whats possible with LiDAR + tweaking

https://sketchfab.com/models/2962f9ad3e794713a963cea79d6e9587
Title: Re: LiDAR mapping
Post by: Prufrock on January 15, 2017, 09:46:53 AM
Pretty handy for terrain ideas, too!
Title: Re: LiDAR mapping
Post by: Imperial Dave on January 15, 2017, 10:16:18 AM
just get a 3D printer as well and voila!
Title: Re: LiDAR mapping
Post by: Dave Beatty on January 26, 2017, 04:00:44 AM
I've used quite a bit of LiDAR in past lives and it is very useful but has limitations - the biggest being it's inability to penetrate foliage. We flew most of our missions in the winter which posed other problems i.e. weather (LiDAR can't penetrate clouds, fog or rain either).

We played around with a form of aerial SONAR years ago and radar still works pretty good as well...

Title: Re: LiDAR mapping
Post by: Imperial Dave on January 26, 2017, 06:39:48 AM
This is true Dave and LiDAR relies on finding gaps in the foliage to enable the laser to find the ground and bounce back to the sensor. Its not perfect but as long as there are some gaps in the canopy of say a wood, then it may allow enough detail to be mapped (depending on the size of the laser as well as the height at which its activated). Also depends on how many pulses per second the laser being used emits.

I have seen some pretty good results of wooded areas using LiDAR recently that made me step back in amazement
Title: Re: LiDAR mapping
Post by: Imperial Dave on March 22, 2017, 10:26:58 AM
nice article on remote sensing techniques (generally) for archaeology.

http://www.archcalc.cnr.it/indice/PDF22/AC_22_Orlando_Villa.pdf
Title: Re: LiDAR mapping
Post by: Chris on March 22, 2017, 10:49:29 AM
Coincidentally, ran across mention of this in the Adams book IN THE LAND OF GIANTS. It was more of  a feature in THE CITY OF THE MONKEY GOD, which recounts an adventure and expedition in Honduras and the discovery of the City of the Jaguar - as it is now called.

FWIW - I would much rather hike along Roman roads in England, Scotland, and Wales, :) than traipse through a snake-infested rainforest filled with mosquitos and sandflies and howler monkeys.  :-\

Title: Re: LiDAR mapping
Post by: Imperial Dave on March 22, 2017, 10:53:39 AM
Quote from: Chris on March 22, 2017, 10:49:29 AM

FWIW - I would much rather hike along Roman roads in England, Scotland, and Wales, :) than traipse through a snake-infested rainforest filled with mosquitos and sandflies and howler monkeys.  :-\

you and me both Chris!  8)
Title: Re: LiDAR mapping
Post by: Nick Harbud on March 22, 2017, 03:05:40 PM
Quote from: Chris on March 22, 2017, 10:49:29 AM
FWIW - I would much rather hike along Roman roads in England, Scotland, and Wales, :) than traipse through a snake-infested rainforest filled with mosquitos and sandflies and howler monkeys.  :-\

Clearly you have never experienced the midges that infest certain parts of the UK on Summer evenings.  These ravenous creatures are quite capable of stripping unprotected flesh to the bone in a matter of minutes...
Title: Re: LiDAR mapping
Post by: Patrick Waterson on March 22, 2017, 06:54:39 PM
... or is that piranhas?
Title: Re: LiDAR mapping
Post by: Imperial Dave on March 22, 2017, 08:10:20 PM
Quote from: NickHarbud on March 22, 2017, 03:05:40 PM
Quote from: Chris on March 22, 2017, 10:49:29 AM
FWIW - I would much rather hike along Roman roads in England, Scotland, and Wales, :) than traipse through a snake-infested rainforest filled with mosquitos and sandflies and howler monkeys.  :-\

Clearly you have never experienced the midges that infest certain parts of the UK on Summer evenings.  These ravenous creatures are quite capable of stripping unprotected flesh to the bone in a matter of minutes...

not in Wales however as the rain is far too persistent and (more importantly) too heavy :)
Title: Re: LiDAR mapping
Post by: Chris on March 22, 2017, 09:59:07 PM
Well, that settles it. I'm staying put and will just continue to read about it and or watch the occasional documentary.

Chris

Title: Re: LiDAR mapping
Post by: Imperial Dave on March 22, 2017, 10:24:58 PM
well in Wales in summer the rain is lovely and warm and no mozzies :)