*Sigh* back at my desk! It’s always a bit of a come down after fieldwork to get back into the office!
We had a brilliant week up in Orkney working between Skara Brae and Maeshowe and meeting with so many interesting people, from on site staff, to archaeologists and artists at our focus group at the college, to Neil Firth at the Pier Arts Centre in Stromness. I really hope my blog entries from last week made some sense…we were working from 8am til 1am most days so there’s a chance I wasn’t at my most coherent!
For anyone who is maybe a little unclear about what we’re doing, simply put we are working collaboratively to produce a short multimedia film which focusses on the journey from House 1 at Skara Brae down the passageways to House 7. Starting from a disembodied perspective contextualising the site from Kieran’s aerial kite photos, moving down into House 1, merging with photogrammetry data and live action footage filmed by Aaron the protagonist will then take a more embodied view and begin to move through Passage A, which will merge with the 3D model (that’s my bag!) and move down Passage B into House 7.
So, the first stage now I’m back in the office is to sort out the Scottish Ten mesh for the site which can then be used to camera match the live footage to, allowing a smooth transition from the site today, to the site as it may have looked like in the past.
To produce the mesh I re-kindled my love/hate relationship with Meshlab, and have to say since the last time I used it (about 2 years ago) the software really has come on in leaps and bounds…still no *undo* button though!
I’ve recently realised my blog gets a far wider readership than I thought so for those of you who aren’t out in the field laser scanning every day I’ll explain a little of the process for you. Laser scanning basically sends out a laser beam which reflects back to the machine when it hits a surface, creating a 3D point cloud which is then taken through a process called “meshing” to produce a solid surface which can then be re-modelled or draped with photo textures from the site.
The more post-processing a mesh is subjected to the less accurate it will become as the software uses algorithms and such to smooth out the surface and fill the holes. However, for the purpose of archaeological visualisation in the context of this project millimeter accuracy takes a back seat and interpretation and aesthetics take the reins! I used Meshlab to tidy up the data and fill some of the holes the scanner couldn’t reach when it was in the field. What’s great about using scan data for a site of this complexity is that it allows for that level of detail in the structures to come across to the viewer. 3D modeling software in general is designed with architects and designers in mind and is very good at straight lines and right angles, but not so good at creating more organic structures – and you don’t get much more organic than the winding passageways and drystone houses at Skara Brae!
Sometimes the more interpretive and engaging side of visualising a site can get a bit lost when you return to the office and begin to process the data. The creative process become linear and systematic once more as datasets are loaded, meshed, tidied up and re-modelled but I’m trying to keep my head in the site and not too much in the software. Parallel with my processing of the meshes for the skeleton model which will hold the whole visualisation together, I’ve been thinking about how to dress the interior of House 7 and modelling up a few artefacts in Mudbox…more on that next week!