Aerial Photography and Visualisation for Built Heritage - PhD Portfolio by Kieran Baxter
Home Portfolio Showreel Publications Map Blog Contact

Saturday 21 July 2012

Jarlshof Reconstruction Sequence Draft 2.1

This is the sequence which I have been using as a basis for the reconstructed elements in 3D, as well as the informing the low aerial angles which I will use for each stage of the short Jarlshof film. I've been lucky to have Alice Watterson contributing to the archaeological reconstruction for the Norse and later phases, allowing me to focus on the environment and atmosphere using the captured photography and photogrammetry, as well as reconstructing the prehistoric phases of habitation.

These early phases will be reconstructed where possible using aerial photography from other better surviving sites such as nearby Mousa Broch, or contemporary reconstructions such as the wheelhouse at nearby Scatness.

Friday 6 July 2012

Completing the Jarlshof Photogrammetry Mesh

The mesh below was created from ten sections of photogrammetry taken with a camera on an eight meter pole in December last year. Although this mesh covers most of the site I was keen to aim for more complete coverage so one of the jobs for my return visit in April was to capture the remaining material needed to fill the holes.



I took a printout of the above plan view of the mesh back on site so that I could target the areas of sparse coverage, highlighted in red. In addition I wanted to extend the mesh into all four corners of the boundary fence and add some low level detail to the enclosed broch wheelhouse structures.



The coloured sections in this images represent the supplementary data captured in April, while the original data is shaded in grey. Over that last few days I've been processing and aligning these sections using the Iterative Closest Point alignment tool in Meshlab. I'm quite happy with the consistency of coverage at this point and the next stage is to stitch these sections together into one seamless mesh.

The original data consisted of 2.8 million vertices and I am adding an additional 0.9 million to that so am expecting the re-meshing process to require even more patience than usual. Once I have a single master mesh this can be broken down into more manageable chunks for texturing and rendering.

St Andrews Kite Aerial Photograph Published in Aurora Magazine



My photograph of St Andrews Cathedral appeared in 'The Big Picture' feature in Aurora, the quarterly customer magazine for Highlands and Islands Airports. This dramatic ruined site makes for a particularly striking low aerial view, although I had to manoeuvre carefully around those lighting conductors!

Monday 2 July 2012

Glenelg Brochs

I took these photographs during a brief visit to Glenelg to add to my collection of broch references and possibly to inform a reconstruction of Jarlshof broch during it's phases of collapse. Among the best preserved examples of brochs on the mainland they are sheltered within a narrow glen, although despite this I was lucky enough to catch some good wind for kite flying.



Capturing this kite aerial photograph of Dun Telve required manoeuvring the kite line around the branches of the large tree on the left, always a frightening experience! It seems only by luck that these huge trees aren't close enough to have damaged the broch structure over time.



As the wind became more unstable I switched to pole aerial photography for this low level shot of Dun Troddan, which lies in clear line of site from Dun Telve. Here a portion of the stairway remains running between the two skins of the wall. The tall cavities supported by spreader stones are what gives these drystone towers their strength.