ArchCamp Four
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ArchCamp Four, York 2008
This page is built from real time notes taken by Kayt during the archcamp, and as such may be inaccurate or missing important things- could participants please go in and clarify any contributions they made or any issues, and also (if they want) provide links to personal webpages and projects etc! I may also have missed peoples names, or misspelled them!
Normally I like to update the wiki in real time, as we talk, but due to the vagaries of technology, we couldnt quite manage this today, so I've added the pages while everything was still fresh in my mind as soon as I got home!
Participants
After a great two days hosted by the University of York, the ADS and Internet Archaeology, the by now usual ArchCamp was held. This year the CAA survivors were (in no particular order):
Leif Isaksen- Southampton Uni
Stuart Eve - L - P : Archaeology
Andrew Larcombe- Birkbeck UL
Michael Charno- ADS
Gary Nobles- ADS
Chris Brayne- Wessex
Claire Louise Kemp - ex-MSc Arch.Comp Soton 2006
Nicole Smith - Uni of Portsmouth (ex-MSc Arch.Comp at Soton 2007)
Paul Cripps- Wessex
Gareth Beale- Southampton Uni
Dave Wheatley- Southampton Uni
Kayt Armstrong- Bournemouth Uni
Jo Cook- Oxford Archaeology
Graeme Earl- Southampton Uni
Joseph Reeves – Oxford Archaeology
Paul Miles - Oxford Archaeology
Sarah Poppy- HER officer for Cambridgeshire
Steve Stead (all sorts of things, but lots of CIDOC CRM especially, and EPOCH)
Blake Williams Glasgow Uni
Anthony Masinton York Uni
Bill Wilcox UEA
Claire (sorry, missed your surnamne Claire- can someone please add this?) VERA /
Nicola Schiavotiello- Southampton Uni
What we got up to
Leif kindly made a short introduction to what an Archcamp is, and we did the round table short introductions, and then got straight into discussing cool stuff!
Firesheds
Blake is working on Battlefield archaeology, specifically looking at 'firesheds' as opposed to viewsheds- a number of antiquisters or colleagues of ours work in this area and are lovely chaps who are happy to talk over the methodologies, so we will put Blake in touch!
Lidar Intensity stuff
Paul Cripps had some interesting things to say about work he is doing with Environment Agency LIDAR data...
LIDAR can be used to generate TIN surfaces or elevation rasters. Data is available in filtered and unfiltered forms. Filtering involves the removal of "first return" data - ie signals returning from tree tops etc - while leaving behind appropriate "last return" data. This should have the effect of removing vegetation and delivering a lovely clean DTM. Unfortunately filtering is something of a black box process and seems to strip some of the archaeological features. Some stripping algorithms are better than others (see Cambridge university unit for landscape modelling) but since we don’t know what algorithms are used here Paul’s been using the unfiltered data.
Simplest use is just to hillshade surfaces from multiple angles to produce geo tiffs.
Paul has been playing with intensity values (laser intensity returned to the kit)- we don’t really know precisely how the value in this field is derived, but it relates to the reflectivity of the point and seems to pick up non-topo data - not all of which correlate with crop marks etc? We aren’t sure what this is picking up red or ir- active IR? Like IR Aerial Photography?
We think the Environment Agency uses a Optech ALTM 3033 LiDAR unit whose spec sheet is given here the laser is certainly IR but no info there on the specific wavelength of the light itself - the class IV specification is only a power output standard.
Dave W's observation that the images produced are without shadows because the source and receptor are effectively coaxial is interesting. Are these images therefore "perfect" IR images?
Intensity data seems to be better for some subsurface features- in Pauls case drainage features.
In discussion it was suggested that A possible step to multiband the image then look at Principal Components Analysis?
File sizes are an issue- grid processes? (Graeme please fill this part in for me!)
Personal Wikis?
Claire Kemp– wiki stuff- do we want her view of a wiki? Claire wanted to know if what she is talking about here is something archaeologists would find useful.
Consensus was YES, in post ex. work especially but pitfalls from probs of breadcrumbs/ navigation.
making users comfortable
graphical representations of pathways through things?
linking to CRM stuff- can we cidoc this from the outset?
markups? or just links? searchability?
versioning in built in wiki’s
in teaching?
we also talked a bit around her ideas about identities and how this links in with the personalised wiki...
Fuzzy 3D
Dave Wheatley wanted to know the following:
Errors in DEMs and effect on viewsheds? Uncertainty in the world- in architecture etc how does this interact with formal methods? Fisher fixed this in viewsheds- error models for dems to introduce the uncertainty- reiterate viewsheds with error simulations…= probability viewsheds…
but in architectural spaces? presence/ absence of architectural elements? window widths re wall paintings visible from street etc.
This is easy in DEMs/ viewsheds- once you make the error models it’s pretty simple in 3D becomes more complex- quite sophisticated changes to primitives within models have big effects- round vs square pillars for example…. does anyone have ways to OO primitives that allows primitives to have methods- pillar can behave as round or oval etc.
Steve Stead suggested the following: COLLADA standard- games engines- OO, objects have classes and behaviours/ instances…
(This all needs a tidy up as I found it hard to follow! Can someone come in and make more sense please, and provide links?)
COOL WEBSTUFF
It is now a tradition to share cool websites, blogs and projects as well, so here are a few things we looked at:
Mike Charno showed us some SVG related stuff about Yosemite national park:
Yosemite SVG and co-ordinates/UTM stuff
He also invited us to read and discuss (on the antiquist list perhaps! an article on slashdot about how wikipedia might 'kill' archaeology: wikipedia and the end of archaeology? (on Slashdot)
Then there were diversions off to strange maps, an excellent blog which compiles wierd and wonderful maps from all over the world and explains some of their history and provenance... and then from there to a webcomic called xkcd, which was deemed sufficiently tangenital to be the last thing we did....
