HOW TO SCAN A BOAT
In many pieces and with much gumption - musing of a 3D scanning novice
You can walk a bit faster. Point the scanner at the object. You are too close. You are too far away.
A few phrases of guidance gently spoken over my shoulder and patiently repeated by Thomas as he was teaching me how to use a structured light scanner. He was a long way from home – Belgium sleepy as he toiled in a warehouse at the height of the Australian summer to train a scruffy bunch of archaeologists the new methods in shipwreck timber recording.
A new, fantastic point of view
When we began looking at the design of the recording and conservation project for the Barangaroo Boat and drawing in the experience and expertise of our network of colleagues actively involved in shipwreck recording and conservation, I got in touch with Dr Toby Jones from the Newport Medieval Ship conservation project in Wales, UK.
I had met him several years ago when I lived in the UK while I completed my Master in maritime archaeology at Bournemouth Uni. Dr Jones (I must ask him if he hates snakes) had undertaken the recording of the Newport ship timbers with a FaroArm/Rhino combo, and I was seeking his insight and advice. Surprisingly, he suggested another method. A new method. And so I met Thomas van Damme.
Thomas was part of the team that developed the Annotated Scans method for recording shipwreck timbers – a much more rapid, yet still highly accurate way of capturing incredibly detailed data – using a Structured Light Scanner/Rhino combo. This work has been published and is available to read open source. Another perk of this method – it is easier to teach.
And that is how we all came to be at the Sydney Metro conservation facility in the summer of 2019, sweating while the music was blaring and bouncing off the walls and the strobe of the scanner pulsed frantically, capturing the remains of one of the oldest known colonial Australian built craft to be excavated, raised and conserved.
Flying solo
“It is easier if you hold the laptop like this. Remember to unclip the battery pack from your hip before you walk away! Give it more geometry.”
I eventually started to get a bit of a handle on it. I remember the first time Thomas walked away and left me to do the scan myself. It’s that mixture of “I’ve got this. I can do it!” and “Please come back – I have no idea what I’m doing!”.
But the real challenge came when Thomas completed his work and set off for home, back to Belgium. Notes, training videos and the phone/email where all there to assist in case of “panic mode” activation.
In order to ensure consistency in the recording of the timbers and use Thomas’ time efficiently, a small team of four archaeologists and one conservator were trained in various aspects of the recording process. However, I had spent the most time learning from Thomas (yeh, ok, that is mostly because I am pretty much part of the furniture) – a protégé, gaining instruction in more functions and techniques of the process. Therefore, upon his departure, undertaking the day to day recording work fell to me.
Bit by bit, mistake by mistake, I developed my style and got into the groove, managing to scan and process more and more timbers per day. As an additional perk, scanning with the Artec scanner, Eva, requires the operator to carry both the scanner and the laptop to which it is connected, giving the biceps, pectoral, back and core muscles a good workout! *flex*
But, it’s not all physical. Once the laps and loops around the object with the scanner have been completed, the raw scans need to be processed. Some software magic turns individual noisy scans into a clean digital representation of the object. Said magic can be tricky business, especially for a novice. Armed with my notes, guiding documents, a fan (one to keep me cool in the summer heat, rather than one to cheer for me), perseverance and a bottomless cup of green tea I managed to tackle the task.
Solving the little issues that would crop up was a great learning experience – for the really confusing ones, I’d reach across the globe and seek the sage counsel of my mentor.
Lessons (learnt the hard way) for Eva scanner newbs
In addition to the technical aspects of learning how to undertake the 3D work on the boat timbers, I picked up on a few more things that made the scanning/processing life easier:
- Keep your belt done up nice and tight – the scanner battery pack that clips to it is not light…
- Have a clean, dry cloth close by to wipe your hands – archaeological timbers are generally mucky and the scanner is white
- Long hair? Tie it back but not in a top bun/knot – the rig for suspending and scanning planks bounces around if bumped…typically, to capture a scan of an object, it must be still – no swinging, no bouncing.
- Do not process scans straight after lunch – the dynamic duo, Pete and Anthony, at Frateli Food are the unsung heroes of the entire project. Their hearty, flavoursome meals were the fuel that kept the cogs turning BUT, after lunch “food coma” is not conducive to good 3D scan processing. Upon occasion I would come-to from a half sleep state to discover I had been processing a scan the entire time! Had to check my work to make sure I had carried out the correct steps. Surprisingly, the answer was yes – looks like I got to the point where I could process ‘in my sleep’.
- Be prepared to do yoga – getting all angles of an object scanned does sometimes mean you have to get into some weird angles
In the end, the team had gained the necessary skills to undertake the rapid capture of objects to the highest acceptable professional standard but the most rewarding part, is knowing that the boat is armed with the best object record for the next stage and for the rest of its life.
My sincerest thanks to Thomas van Damme – it has been a privilege to work with you and I look forward to future collaboration. In addition, we acknowledge the work of Sydney Metro and its staff, without whose support this project and all that it enables, would have never come to be.