Part 3 – Sources and Paradata

Before going into the bulk of how to model an archaeological site and why do it, I would like to spend a moment discussing the research that should be at the basis of the model itself. The fact that 3D Reconstruction is in its infancy brings many advantages and disadvantages to the table. On the one part, it is exciting to think there is so much we do not know as it means endless applications are there just waiting to be discovered. On the other hand however, there is a distinct lack of consistent methodology between projects and while some publication are clearly founded on extensive research (Dawson et al. 2011 amongst many others), others seem to be more loosely interpreted.

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Fig.1 – The first steps in modelling, based on a plan of the site to scale.

This is one of the reasons behind ‘paradata’, a term that has recently been applied to the field. To understand paradata we need to first discuss metadata. Especially in computer science, many authors have lamented the inability to replicate experiments involving code (Hafer and Kirkpatrick 2009; Boon 2009; Ducke 2012; Hayashi 2012). In the words of Marwick:

“This ability to reproduce the results of other researchers is a core tenet of scientific method, and when reproductions are successful, our field advances (Marwick 2016, pp.1).”

and

“A study is reproducible if there is a specific set of computational functions/analyses (usually specified in terms of code) that exactly reproduce all of the numbers and data visualizations in a published paper from raw data (Marwick 2016, pp.4).”

Essentially the debate is that publishing results is not enough, but that instead we should include additional information, such as settings used in a program or the raw code. This collection of information is referred to as ‘metadata’. Some authors on the other hand have taken it a step forward, arguing that we should include descriptions of the process, a discussion of the choices made and the probabilities (Denard 2009; Beacham 2011, D’Andrea and Fernie 2013). This ‘paradata’ is best described in the London Charter, which is the first attempt to creating a methodology in 3D Reconstruction:

“Documentation of the evaluative, analytical, deductive, interpretative and creative decisions made in the course of computer-based visualisation should be disseminated in such a way that the relationship between research sources, implicit knowledge, explicit reasoning, and visualisation-based outcomes can be understood (Denard 2009, pp.8-9).”

Given that a major critique in 3D Reconstruction is accuracy (Miller and Richards 1995; Richards 1998; Devlin et al. 2003; Johnson et al. 2009), paradata is our way to defend ourselves. While it is impossible to create the perfect model, by demonstrating the process behind the reconstruction allows a user to understand the interpretation given and draw their own conclusions.

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Fig.2 – A highly speculative Roman Villa. Without knowledge of the process it is impossible to know how accurate each element is.

One of the elements we have mentioned previously are sources. While the process itself has to be methodical in order to gain accurate results, the sources provide the wireframe upon which the interpretation can take place. It therefore essential that the sources are well researched and well documented. For this purpose I like the classification proposed by Dell’Unto et al. (2011), which sees different categories based on accuracy:

  • Reconstruction by Objectivity: sources based on in situ elements, like plans, 3D scans, archives.
  • Reconstruction by Testimony: illustrations, literary sources, notes.
  • Reconstruction by Deduction: elements that can be deduced from in situ remains, but that are not actually there.
  • Reconstruction by Comparison: based on other sites, this is actually quite an important one as a lot of features carry on between remains of the same regions.
  • Reconstruction by Analogy of Styles: especially for decoration, looking at other stylistic elements that have been preserved can help make the whole model look more realistic.
  • Reconstruction by Hypothesis: an essential part of reconstruction, but the most inaccurate.

Of course, the more we go down this ladder, the more inaccurate the sources are. Yet it is by combining all the different sources that we get the finished model. Paradata can help with determining which sources were used for each part of the model, and therefore provide information of the model as a whole.

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Fig 3 = Partly completed model of a Greek house, based on plan, excavation reports and site comparison.

In conclusion, there are many sources that can be used when constructing a model and although some are more precise than others, all of them contribute to the final result. If they are applied methodologically and the process is recorded, we can provide an accurate and reliable reconstruction.

Over the next posts I will start looking at SketchUp for modelling, although the ideas will carry over to other software such as 3Ds Max.

REFERENCES:

Beacham, R. C. (2011). Concerning the Paradox of Paradata. Or, “I don’t want realism; I want magic!”. Virtual Archaeology Review Vol.2 No.4 pp.49-52.

Boon, P., Van Der Maaten, L., Paijmans, H., Postma, E. and Lange, G. (2009). Digital Support for Archaeology. Interdisciplinary Science Reviews 34:2-3 pp.189-205.

D’Andrea, A. and Fernie, K. (2013). CARARE 2.0: a metadata schema for 3D Cultural Objects. Digital Heritage International Congress Vol.2 pp.137-143.

Dawson, P., Levy, R. and Lyons, N. (2011). “Breaking the fourth wall”: 3D virtual worlds as tools for knowledge repatriation in archaeology. Journal of Social Archaeology 11(3) pp.387-402.

Dell’Unto, N., Leander, A. M., Ferdani, D., Dellepiane, M., Callieri, M., Lindgren, S. (2013). Digital reconstruction and visualisation in archaeology: case-study drawn from the work of the Swedish Pompeii Project. Digital Heritage International Congress pp.621-628.

Denard, H. (2009). The London Charter: for the computer-based visualisation of cultural heritage.

Devlin, K., Chalmers, A. and Brown, D. (2003). Predictive lighting and perception in archaeological representation. UNESCO World Heritage in the Digital Age.

Ducke, B. (2012). Natives of a connected world: free and open source software in archaeology. World Archaeology 44:4 pp.571-579.

Hafer, L. and Kirkpatrick, A. E. (2009). Assessing Open Source Software as a Scholarly Contribution. Communication of the ACM Vol.52 No.12 pp.126-129.

Hayashi, T. (2012). Source Code Publishing on World Wide Web. International Conference on Advanced Information Networking and Applications Workshops pp.35-40.

Johnson, D. S. (2009). Testing Geometric Authenticity: Standards, Methods, and Criteria for Evaluating the Accuracy and Completeness of Archaeometric Computer Reconstructions. Visual Resources 25:4 pp.333-344.

Marwick, B. (2016). Computational Reproducibility in Archaeological Research: Basic Principles and a Case Study of Their Implementation. Journal of Archaeological Method and Theory pp.1-27.

Miller, P. and Richards, J. (1995). The Good, the Bad, and the Downright Misleading: Archaeological Adoption of Computer Visualisation. In: Huggett, J. and Ryan, N. Computer Applications and Quantitative Methods in Archaeology. Oxford: Tempus Reparatum pp.19-22.

Richards, J. D. (1998). Recent Trends in Computer Applications in Archaeology. Journal of Archaeological Research Vol.6 No.4 pp.331-382.

Part 2 – 3D Reconstruction Literature

In this section I would like to go through some projects I have been reading about that I think are very useful for understanding 3D Reconstruction in Archaeology. Before delving into the practicalities of the technology it is important to assess where the field is at right now.

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An image from Champion et al. (2012) showing the reconstructed city of Palenque.

If you look through the literature, 3D Reconstruction is often scarcely documented and results are limited. The three major critique points I have encountered are to do with accuracy, lack of human element and on use. Here is a brief overview:

  • Accuracy: studies lack background information on how the model was achieved, and create the false idea that the reconstruction is absolutely certain, while often it is simply one of many interpretations.
  • Lack of human element: based on Thomas (2004a; 2004b) and Tilley (2004), 3D Reconstruction is seen as a purely visual subject, alienated from human experience.
  • Use: 3D modelling is used simply to present sites, and are seen as add-ons. In reality, they provide great scope for interpretation.

The first paper I would like to mention is “Digital reconstruction and visualisation in archaeology” by Dell’Unto et al. (2012). On the subject of accuracy in 3D Reconstruction, Dell’Unto et al. propose the use of a series of levels of reconstruction: by identifying and recording the sources for each portion of the model, it is possible to assess the relative accuracy of each part. The first level of reconstruction is based on in situ elements, which are nearly certain, while the last level is dedicated to purely hypothetical reconstructions. This is a great approach as it means the modeller is accountable for the model, but at the same time they have the freedom to experiment as it is clear from the recording what they have done.

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Levels of reconstruction by Dell’Unto et al. (2012).

On the topic of human experience, I can mention a few papers that implicitly refute the ideas proposed by Tilley and Thomas. While 3D modelling is indeed an exceptionally visual subject, it is not simply about looking at images. An entire current of thought deals with ‘presence’, the feeling of belonging a person gets when exploring a 3D environment. It seems that people get involved with the models to the point they ‘experience’ them, as if they were present on site. So while Tilley and Thomas refuse Visualisation as they prefer to explore the site in first person, I would argue that you can do that with 3D Reconstruction. An author I have come across which deals with ‘presence’ is Ch’ng (2009; Ch’ng and Stone 2006; Ch’ng et al. 2011), although I think the forerunner of this field is Chalmers (2002; Chalmers and DeBattista 2009; Devlin and Chalmers 2001; Devlin et al. 2003; Gutierrez et al. 2006). He has made exceptional steps in recreating archaeological sites with near perfect realism, in order to increase the sense of ‘presence’ people experience. His work on illumination is unmatched, and his articles are well worth a read.

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Different lighting effects as studied by Chalmers and DeBattista (2009).

Additionally the work of Dawson and Levy (2006; Dawson et al. 2007, 2011, 2013) are an exceptional testimony of how people respond to 3D environments. They recreated a Thule hut and then invited some members to explore them, recording their reactions and showing their emotional attachment.

Dawson and Levy are also prime examples of 3D Reconstruction being used for interpretation, as their analysis of hut building showed that there was significant reuse of bone structures. Many others have explored the utility of this type of technology, so it is hard to pinpoint individual papers of significance. Champion et al. (2012) use gaming software to educate users on the archaeology of the Palenque city. This is by far one of the best studies I have encountered, and I believe they are the forerunners of ‘serious games’ for archaeology.

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Another view of the ‘serious game’ by Champion et al. (2012).

Similarly the work of Forte et al. (2012) shows much promise in the same area. Finally, the work of Murgatroyd et al.(2011) is not strictly related to reconstruction, but the simulations they have run on Byzantine army movement is very important for understanding the reach of scripting, which can be combined to 3D reconstruction.

I hope this has provided you with an overlook of all the potential applications of 3D software. Over the next couple of weeks I aim to outline the reconstruction process, in order to open up the path to scripting.

 

REFERENCES:

Ch’ng, E. and Stone, R. J. (2006). 3D Archaeological Reconstruction and Visualisation: An Artificial Life Model for Determining Vegetation Dispersal Patterns in Ancient Landscapes. Proceedings of the International Conference on Computer Graphics, Imaging and Visualisation.

Ch’ng, E. (2009). Experimental archaeology: is virtual time travel possible? Journal of Cultural Heritage 10 pp.458-470.

Ch’ng, E., Chapman, H., Gaffney, V., Murgatrayd, P.. Gaffney, C. and Neubauer, W. (2011). From sites to landscapes: how computer technology is shaping archaeological practice. IEEE Computer Society 11 pp.40-46.

Chalmers, A. (2002). Very realistic graphics for visualising archaeological site reconstruction. Proceedings of the 18th Spring Conference on Computer Graphics pp. 7-12.

Chalmers, A. and DeBattista, K. (2009). Level of realism for serious games. 2009 Conference in Games and Virtual Worlds for Serious Applications pp.225-232.

Champion, E., Bishop, I. and Dave, B. (2012). The Palenque project: evaluating interaction in an online virtual archaeology site. Virtual Reality 16 pp.121-139.

Dawson, P., Levy, R., Gardner, D. and Walls M. (2007). Simulating the Behaviour of Light inside Arctic Dwellings: Implications for Assessing the Role of Vision in Task Performance. World Archaeology Vol.39 No.1 pp.17-35.

Dawson, P., Levy, R. and Lyons, N. (2011). “Breaking the fourth wall”: 3D virtual worlds as tools for knowledge repatriation in archaeology. Journal of Social Archaeology 11(3) pp.387-402.

Dawson, T., Vermehren, A., Miller, A., Oliver, I. and Kennedy, S. (2013). Digitally enhanced community rescue archaeology. Proceedings of First International Congress on Digital Heritage pp.29-36.

Devlin, K. and Chalmers, A. (2001). Realistic visualisation of the Pompeii frescoes. Proceedings of the 1st International Conference on Computer Graphics, Virtual Reality and Visualisation pp.43-48.

Devlin, K., Chalmers, A. and Brown, D. (2003). Predictive lighting and perception in archaeological representation. UNESCO World Heritage in the Digital Age.

Dell’Unto, N., Leander, A. M., Ferdani, D., Dellepiane, M., Callieri, M., Lindgren, S. (2013). Digital reconstruction and visualisation in archaeology: case-study drawn from the work of the Swedish Pompeii Project. Digital Heritage International Congress pp.621-628.

Forte, M., Lercari, N., Onsurez, L., Issavi, J. and Prather, E. (2012). The Fort Ross Virtual Warehouse Project: A Serious Game for Research and Education. 18th International Conference on Virtual Systems and Multimedia pp.315-322.

Gutierrez, D., Sundstedt, V., Gomez, F. and Chalmers, A. (2006). Dust and light: predictive virtual archaeology. Journal of Cultural Heritage 8 pp.209-214.

Levy, R. and Dawson, P. (2006). Reconstructing a Thule whalebone house using 3D imaging. IEEE MultiMedia. Vol.13 No.2 pp.78-83.

Murgatroyd, P., Crenen, B., Theodoropoulos, G., Gaffney, V. and Haldon, J. (2011). Modelling medieval military logistics: an agent-based simulation of a Byzantine army on the march. Computational and Mathematical Organization Theory Vol.18 No.4 pp.488-506.

Thomas, J. (2004). Archaeology and Modernity. London: Routledge.

Thomas, J. (2004). The Great Dark Book: Archaeology, Experience, and Interpretation. In: Earle, T. and Pebbles, C. S. A Companion to Archaeology. Oxford: Blackwell Publishing pp.21-36.

Tilley, C. (2004). The materiality of stone: exploration in landscape phenomenology. Oxford: Berg.

Roman Villa Reconstructed In 3D

Based on the plan of an actual Roman Villa, this is a fly through of the model. It’s a way to explore this living area and get a more authentic feel of what it would have been like to actually live in the Roman times.
The model was made using Google Sketchup, and the final project sees furniture and details added in to make it even more realistic. This however is the building at present, showing how archaeology can be brought to life using 3D modelling software.
A more detailed account on how this model was made can be found previously on this website.

Roman Villa Reconstruction Preview

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I have talked endlessly before on this blog about the use of Google Sketchup in the archaeological world, so pardon yet another example on the topic. I recently started recreating a typical Roman Villa using plans from a number of sites and any source of information I could find. The final plan is to not only create the structure itself, but also include many more details, such as furniture, statues, etc.

Having completed the main structure I thought I would share the results as they stand, as a sort of preview to the completed work, and explain some of the aspects of making the model. In the next couple of days I’ll also post a fly-through video which is currently rendering, to give an even better impression.

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This model was an interesting one to make, as it was more complex in some aspects than the ones I did before, and it combined opened and closed spaces, with equal importance given to both. The plans I found were very good for the ground floor, which is pretty accurate, but for the top floor there is a definite lack of information, mainly due to the lack of archaeological evidence. Therefore I had to resort to sketch reconstructions which are based on personal interpretation, which I am not usually fond of. Similarly the roof and the inside of the rooms is mostly conjecture on my part, based however on ideas found in texts. Overall then the model is much more interpretive than for example the Parthenon model I made, but at the same time it is more useful as the Parthenon is actually standing, while the villa is not.

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Something I noticed from making this model is the efficiency with which Sketchup deals with lighting. In the past I wasn’t a big fan of the lighting conditions as I found that inside spaces were too dark, and outside spaces were too bright, however in this case I find that this is in no way an issue, possibly because we have both inside and outside. The rooms are still a bit dark, but with the addition of external windows that I’m adding in the next phase, they should be quite faithful to reality, while the internal courtyards are bright, but not unnaturally so. As a whole the results are quite satisfying, and when objects are placed within the model they will also look realistic due to this.

ImageAlso , rounded edges tool is still a favourite of mine, but I now use it less frequently. In large models some walls look more realistic with rounded edges, but not everything does. Door frames for example look equally good without, and given that it effectively adds many more lines to the model, there is really no need to round them off. For walls, I found that adding a slight slope at the bottom really makes it less blocky and much nicer to the eye. On a more practical note, creating components is still the greatest tip I can give with Sketchup. I found that making each floor and roof a separate entity made it much easier to edit, as you could hide upper floor when having to edit the lower one, and vice versa.

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As mentioned before, as soon as the animation finishes rendering I shall post a new update. I realise that recently I have been posting less and less, but I assure you it is only for practical reasons. I am currently involved in the writing of an archaeological based radio show, which is taking up a lot of my spare time, as well as working on a number of sites. Also these models do take their time to be made, so I’d rather wait a bit and publish something good rather than many very random posts. Finally a few of the projects I have been working on have the disadvantage that I can’t actually publish any of the results, which means there are a few things that I am doing that I can’t write about specifically. Therefore I apologise if sometimes it takes a bit longer to post something new.

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Sketchup for Archaeology – Olynthus House

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Having talked for the last few days about Sketchup and its uses in Archaeology, I thought I’d complete this line of enquiry by showing you another model I made during my second year and briefly presented before, a house from the Classical Greece site of Olynthus.

Much like the houses of Zagora I covered before, the house at Olynthus is a great example of domestic space in the classical world, with an inside courtyard and different rooms of which for the larger part we know the function. The reason or Olynthus in particular is that in this case the houses have all the elements of houses in the Classical period, and the base plan is repeated throughout the entire town.

House 6

The main reason I chose this model was that it was a challenge. Previously I had only reconstructed the Parthenon, so I was not entirely used to closed spaces. In addition, I had the actual site reports handy, which meant I could reconstruct the house reliably, with little left to imagination. Finally, it gave me a chance to investigate issues of lighting within closed spaces, and settle a debate that I’d read about, regarding a possible need of a flue to provide lighting to some of the rooms.

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Apart from the use of components, that I’ve discussed already, I found two interesting things with this model: the use of visualisation to understand the use of space, and the aforementioned lighting tool.

One of the main issues I was having with the house was the presence of a ladder, which would have allowed transit to the upper stories. The location I originally intended for it didn’t actually fit, something that I only realised when looking at an initial draft of the model. It was too steep, and if it extended any further to reduce this it would have blocked one of the doors. Therefore I decided that the location had to be wrong, and tried many different positions that could be possible. The one I finally settled with was the only one that “looked” right, and after reading the report again it turned out there was a base for the ladder in some of the houses in that exact spot.

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This is probably insignificant on the long term, but it made me think that the only way I realised the position was wrong was with the added dimension, as the 2D plan didn’t give me sufficient information to realise.

The issue with lighting was part of a debate I was reading, about an area of the house interpreted as a flue. Some suggested this area was open at the top, in order to allow lighting, while others thought that the lighting in the room was sufficient to carry out basic activities. I therefore created an entire street by repeating the house, and placed windows as suggested by the report. I then rendered the images with and without a hole in the ceiling.

dark oikoslight room 2

The results are not of the most conclusive, although there is a difference between the two rooms. This does however suggest that a hole in the roof would have not been sufficient, so it is possible the flue was used to conduct smoke from a fire within the room.  Again, in this particular instance the results are not ideal, but in other models the idea may have more success, especially in enclosed spaces.

Sketchup and Archaeology – Iron Age Roundhouse

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One of the projects I’ve been working on has been reconstructing a roundhouse we found at Caerau, Cardiff, using Sketchup to create the main frame, and V-Ray to render it as an image. This will then be used to fade over some footage of the archaeological site, to show a transition between what we can see and what would have been present on site.

For this purpose I created a very basic roundhouse model, coupled with a fortification mound and a sheer drop behind it. All of this was based on the GIS data I had of the site, so it does represent what we actually found on site.

The model itself is pretty simple, but it gave me a chance to play around with a few different elements of Google Sketchup, which will then be useful for more complex models. In particular I was looking at the application customised textures, the creation of backgrounds, and the use of rounded corners to create realistic mounds.

Customised textures is one of the main points of 3D modelling, and is extremely useful to give the model a more realistic feel. The problem is that it is really hard for someone as artistically challenged as myself to create good textures, so I resorted to using a combination of pre-made ones instead. I used Photoshop to layer three different grass materials, and I rendered patches of each more opaque, to create many different coloured patches. This made the ground surface on the model much more realistic, as it’s  not a repeating pattern any more, but a more complex and varied one, with different shades in different areas.

I then realised that one of the elements that really made the model lack realism was the background. The Sketchup standard rendering mode is to create a background that looks like the sky, which with particular angles is fine, but that becomes a problem if we want to get specific images, like in this case.

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Therefore at first I decided to create a large cylinder shape around the entire model, and then paint it using a stock image of a panorama found online. This failed as the cylinder is actually made of many different faces, each of which started the texture from the origin point, thus making it repeat. Therefore I decided to use a flat surface instead, creating a sort of shield I could move around where needed, and that could be placed in the background of the rendered image much like a green screen in video editing.

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Finally, The mound itself looked extremely blocky, as Sketchup is not ideal when it comes to rounded surfaces. I tried using the Rounded Angle Plugin that I’ve mentioned before, and made the area of impact quite large. The result was exactly what I wanted, as it created a much more realistic mound, although it’s not ideal for the base, which can be a problem from some angles.

Overall I think these three tips are really useful, and I shall be using them from now onwards to create better large scale models, and especially to simplify and improve the rendering process.

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Creating a 3D Model of the Town of Zagora with Sketchup

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Sorry it took me so long to write a new post, I’ve been swamped with work the last few days. I am however back and will be resuming my daily posting. Today I want to show you a few models I created earlier on this year for one of my essays, regarding the town of Zagora, in Greece.

The essay itself was about the evolution of housing in Greece during the Archaic Period, and the town of Zagora was particularly important due to the distribution of space and especially open areas within the houses, which become a prominent feature of Classical Greece houses. The town was made of original smaller houses that were later expanded, creating agglomerated areas, with many houses sharing common walls with other houses. The exact details of the process, and the conclusions we could deduce from this have currently been placed in a location within my mind that I cannot reach, and the original essay is similarly lost within my laptop, but the main idea that got me to create a model of the entire town was that of space visualization.

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3D modelling of structures is entirely about bringing spaces to life, in order to learn from them in a much more efficient way than in 2D. A plan of a town is great to find patterns of activity, but to get an actual idea of how the space was arranged, a model is much more efficient. So in order to really show what on paper was simply a theory I decided to recreate the town from the plan, and also to concentrate on a few of the houses for better examples. These houses were made first without the later additions, and then with them, to show how the creation of open courtyards would have made it easier to carry out activities, as well as giving a more private feel to the environment.

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The models themselves were easy to make using Google Sketchup, and given that this was more interpretive than for presentation, I was able to create it in around 4 hours, showing that good results are obtainable with little effort. Had I had more time I could have used the Rounded Corners tools, and added more detail within the structures, as well as making the outsides more realistic with better textures.

In addition to the large scale reconstruction, which was a first, I also learnt a lot in these models about component placing within Sketchup. If a certain feature of a model is something you believe you may use in the future, it is worth saving it as a component. This can then be uploaded in another model to save time, and very complex objects can be avoided. In this case I used a roof I had already created to cut on the creation time, as well as small figurines I found online to show the scale of the buildings in the essay.

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Overall these models also show how Sketchup can be a real help to display visual elements to enhance the understanding of certain concepts.

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New Things I’ve Learnt for Google Sketchup

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If you read my blog yesterday I posted an article about creating a virtual museum using 123D Catch and Google Sketchup Pro. Apart from the large scale project, this has also given me a chance to play around more with these programs, and especially with Sketchup. As a result I’ve learnt a few more skills I’d like to share with you.

Sketchup is a brilliant program, and in my opinion the easiest and most efficient 3D modelling software for archaeology. For other uses it could be a but simplistic, especially when realism is an issue, but for creating models of sites or structures for display it is sufficiently capable. I currently have Sketchup Pro, as well as V-Ray for rendering images, but there is a free version of Sketchup that has most of the functions of the Pro version and that is sufficient for most models. The tips in this article though are based on the Pro-Vray combination, although some of them should still be available in the free version.

Materials: One of the things I was trying to achieve in the museum was creating little tags for objects, in which I could display information. Because I didn’t really need to write the actual text, to see if it would work I got an image of text from the internet and then loaded in the paint tool. I’d done this before, but I was having trouble making the text fit perfectly. After trying different approaches I noted there was a “position” material tool when I right clicked the surface. This opened up a nice interface which allowed me to successfully position the image. Saved me a lot of time, and it has good potential for other things too. One of the ideas I was thinking was to create a large circular wall around a site onto which I could paint a landscape, so when it was rendered it gave the impression of being place in the real world. The positioning tool would allow me to manipulate this texture in order to make it continuous, without having to play around with the scale.

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Lighting: I finally used the lighting tool with V-Ray, which was harder to understand than I thought, This was the first time I created an entirely internal space, and lighting was an issue. By creating a long thin rectangle, and placing the light on one side I created a convincing neon light. The trick here was increasing the intensity to 150, rather than the measly 30 it is at, which makes it seem like it is not working. I am also honestly impressed with this tool, it does add a lot to the realism, and I’m even thinking of adding a few lights under objects to give them a lit up effect.

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Walk tool: I usually pan and zoom and use the orbit tool when I’m editing and when I’m showing people my work, but the walk tool is a much nicer way to present a model. It allows the user to feel like they are present on the site rather than an external viewer, and it’s much less shaky than I thought, You can even make it so that it will automatically stop when you encounter a surface which is great, considering on occasion this is an issue with the orbit, pan and zoom tools.

Obj importing:  Didn’t realise that Sketchup could import object files, which is great. Many 3d programs have difficulty with the material files associated with the 123D Catch obj files, yet Sketchup seems to have none. It is hard to alter the files themselves, yet it’s a good way to put them in context. A feature could be placed within the reconstructed model of the site, and if all of the features were recorded they could be glued together to make the entire site.

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Glass: I made a few glass cabinets for the virtual museum and then tried making them transparent. I painted them light blue and then set the opacity to 18, making them only slightly visible. When rendering the images, this created a big problem, as for some reason the outer side of the glass was transparent, while the inner was reflective, creating an odd mirror effect. I had to Google this one, and the solution seems to be to give the surface at least a bit of thickness. By creating a 3D pane of glass, rather than just a 2D surface of glass the problem is solved, with realistic effects

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Some of these tips are probably obvious, however being self taught in the program means that I have gaps in some areas. However the good thing of Sketchup is it requires little knowledge, just a keen interest.

Virtual Museums: Combining 3D Modelling, Photogrammetry and Gaming Software

I wrote the post below yesterday night, but since it was written I’ve managed to create at least a part of what is described in the text, which is shown in the video above. Hence keep in mind that the rest of the post may be slightly different from what is in the video.

One of the more popular posts I’ve published seems to be the one about public engagement at Caerau, South Wales, in which I created an online gallery with the clay “Celtic” heads school children made. The main concept that I was analysing in the text was the idea that we could create digital galleries in which to display artefacts,

When I wrote the word gallery I imagined the computer definition of gallery, as in a collection of images (or in this case models) within a single folder. However I have since found this: http://3dstellwerk.com/frontend/index.php?uid=8&gid=18&owner=Galerie+Queen+Anne&title=1965%2C85%C2%B0C

This is an example of what the website http://3dstellwerk.com offers, an opportunity for artists the create a virtual space in which to display their work. It allows users to go “walk” through the gallery and view the 2d artwork as if it were an actual exhibition. Although the navigation may require a little improvement, it is a brilliant idea to make art more accessible to people.

Virtual Museum

This idea however could easily be adapted for archaeology, using Photogrammetry, Making models of a selection of artefacts using 123D Catch, we can then place them within a virtual space created with our 3D software of choice, in order to then animate it using gaming software such as Unity 3D which would allow user interaction. A large scale project could even allow the objects to be clicked in order to display additional information, or create audio to go with each artefact. Video clips could also be incorporated within the virtual space.

Virtual Museum 2

On an even larger scale this could mean we can create online museums available to all and with specific goals in mind. As we are talking of digital copies of objects, it would be possible to group in a single virtual space a number of significant objects without having to physically remove them from their original location.

The only problem that we may encounter with this idea is file size, as each photogrammetric model is relatively small and manageable, yet if we want a decent sized virtual museum we are going to need a large portion of data. Still, even if the technology at present is not quite capable of dealing with the bulk, the rate at which it is improving will allow such ideas to be doable in the near future.

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The Winged Victory of Samothrace Reconstructed Digitally Using Tourists’ Photographs.

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If you’ve been following my latest attempts to recreate famous monuments through Photogrammetry, using nothing but tourists’ photographs finally I have something to show for your patience. Before you get your hopes up, it is still not perfect, but it’s a step forward.

The idea behind this is that 123D Catch uses photographs to create 3d models, and while generally this entails that the user has to take their own photographs, it doesn’t necessarily have to be so. The internet is full of images, and while most of them seem to be of cats, there are many images of famous monuments or of archaeological finds. Therefore there has to be a way to utilise all these photographs found online to digitally recreate the monument in question. The problem is, although theoretically there should be no issue, there are still a great number of elements that affect the final mesh, including lighting, background and editing. While the images the user takes in a short span of time remain consistent due to minimal changes taking place, a photograph taken in 2012 is different from one taken in 2013 by a different camera, making it hard for the program to recognise similarities. As an addition to this, tourists take photographs without this process in mind, so often monuments are only photographed from limited angles, making it hard to achieve 360 degree models.

In order to better understand the issue I started working with a series of monuments, including the Sphinx, Mount Rushmore (see previous articles), Stonehenge and the Statue of Liberty. These however are extremely large monuments, which makes it somehow more difficult for the program to work (although theoretically all that should happen is a loss in detail, without affecting the stitching of the images). Therefore I decided to apply my usual tactic of working from the small to the large, choosing a much smaller object which would still prove the idea. In this case I chose the Winged Victory of Samothrace.

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The reasoning behind the choice is that unlike other statues, there is more of a chance of images from the sides being taken, due to the shape of it. It is also on a pedestal, which means background should remain consistent in between shots. It also allows good contrast because the shadows appear amplified by the colour of the stone. I was however aware that the back of it would probably not work due to the lack of joining images, but figured making the front and sides itself would be sufficient progress.

The results can be seen here: https://sketchfab.com/show/604f938466ad41b8b9299ee692c5d9a3

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As you can see, the front and most of the sides have come out with enough detail to call it a success, also because 90% of the images taken from these angles were stitched together. The back as predicted didn’t appear, and there are some expected issues with the top as well. What however is even more surprising is that some of the images taken had monochromatic backgrounds, very different from the bulk. These images still stitched in, suggesting that background is not the key factor with these models. The lighting is relatively consistent, so it could be this is the main factor. As for image size and resolution there doesn’t seem to be much of a pattern.

Overall I was very pleased with the results, and hopefully it’ll lead to a full 360 degree model as soon as I pinpoint an object with enough back and side images. Still, this does show that it is possible to create models from tourists’ photographs, which would be great to reconstruct those objects or monuments that have unfortunately been destroyed.

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