26th April 2012, 03:51 PM
kevin wooldridge Wrote:Yep Jack is right....photograph the damn cobbles/burial mound/prehistoric mortuary enclosure...use the GPS or total station to zap in a few randomly placed targets, georeference and then digiitise the rectified photos at your leisure.....
I know the thread's moved on from the hand drawn/rectified photograph/EDM or GPS planning discussion, but I thought people might find these 3D Laser Scanned plans that I just came across to be of interest. I'd not previously seen such technology used on a commercial site - apparently relitively cheap and speedy.
As with everything using the right technique for the right situation is key, but the results look pretty impressive. It's not a technique I'm that familiar with - I'll have to go off and do a bit of background reading.
Quote:The complex nature of these industrial structures meant that recording by conventional survey and planning methods would be expensive on time and labour. The survey firm J C White was brought in to record the furnaces using laser scanning technology, a method that has only become practical for use in archaeology during the last few years. The laser scanner emits thousands of laser pulses a second and as it traverses the site, records the time taken for each pulse of the beam to be reflected off any solid surface, from which in turn, each distance can be calculated to a few millimetres? accuracy. Setting up the equipment in different locations thus allows what is termed a ?point cloud? to be constructed, a virtual 3D image of the solid artefact that can then be manipulated with computer software to form an accurate plan, sections or a 3D model. Using this technology, Areas C and D were surveyed within a day.Preliminary data:
http://www.canterburytrust.co.uk/catpres..._AREA2.jpg
3D Oblique view of the 3D model:
http://www.canterburytrust.co.uk/catpres..._area1.jpg
Full details of the project can be seen here - http://www.canterburytrust.co.uk/news/pr...aper_mill/