fbpx
Connect with us

Community

Adventures in Picture Making

Photogrammetry is one of the new tools that is revolutionizing marine archaeology and enabling explorers to share their discoveries with scientists and the public alike. Seattle tekkie Kees Beemster Leverenz discusses some of the methods he and his team-mates have worked through to bring back home the image, err data. You won’t believe your eyes!

Published

on

by Kees Beemster Leverenz

The SS Thistlegorm

Marcus Newbold and I found ourselves in the cargo hold of the Thistlegorm, a World War II steamship that’s famous for being packed to the brim with antique motorcycles, trucks, and weapons. Our goal was simple: take just one photo that did justice to the sheer volume of material in the ship. The Red Sea is warm, the SS Thistlegorm rests in shallow water, and we were both equipped with rebreathers, so we had practically all day to set up the shot. 

The plan was to set up a makeshift photo studio 100 ft/30 m underwater in a rusty ship. After an afternoon of begging, we scraped together a half dozen video lights and a couple super-bright strobes from our friends that had come along with us. We arrived in the cargo hold quickly and began the methodical process of placing and adjusting lights for the best effect, careful to avoid stirring up any silt. 

I’d occasionally hear Marcus say something through his rebreather mouthpiece as he worked his way around the hold placing his lights, lighting up the two pickup trucks that dominated the space. While it’s never entirely clear what anyone is saying when they try to talk through a mouthpiece, you can usually tell if someone’s happy or sad, excited or mad. Even without turning around, I could hear from the tone of his muffled words that he was pleased with how his half of the lighting job was shaping up.

Although Marcus seemed pleased, I was having a lot of difficulty. One light in particular was causing me grief, and it was key to getting the photo we imagined. It was the most powerful off-camera light we had, and it needed to be positioned in exactly the right orientation or it wouldn’t go off. After several minutes of adjusting, I managed to wedge it in exactly the right spot. The room was lit, and it was time for Marcus to take his place in the center of the room for the picture. 

Unbeknownst to me, Marcus had adjusted his weight right before the dive, and was having trouble getting comfortable in the water. His buoyancy just wasn’t quite right. So, instead of floating motionless for the picture (like he’d done the previous few days), he started swimming laps. I took a series of photos, but none was exactly right. Every time, there was something wrong with the picture: either Marcus was too far away, or he was too close. His eyes weren’t in focus, or the lights didn’t go off. 

Amidst the controlled chaos of the photoshoot, a group of divers from another boat swam into the cargo hold to explore. We’d spent nearly an hour in one of the world’s most popular wrecks, so we couldn’t expect to spend the entire day alone. However, we weren’t planning on them making any changes to our set!

To my horror, I watched from across the room as one of the divers reached down and picked up my carefully wedged strobe: the one that needed to be in exactly the right spot to work. He turned it over in his hand curiously, unaware of what he’d just done. An instant passed, and then I heard a funny sound from the other side of the room. It was the sound of pure frustration emanating from Marcus, believing that this diver had accidentally ruined our set. While his voice was muffled by his rebreather, the emotion was crystal clear. 

I wasn’t the only diver to hear the noise, and our new friend’s curiosity immediately vanished. The diver quickly replaced the light, Marcus’ initial reaction subsided, and fortunately we only need to make a few quick adjustments to get the shot. The six video lights and three strobes we used for the final image allowed us to capture the depth and the breadth of the room, while keeping Marcus and the 40’s-era trucks well lit. That simply wouldn’t be possible with only the lights attached to the camera.  

Off-Camera Lighting

Using off-camera lights is challenging; it’s much easier to mount your lights on your camera and be done with it. However, breaking free of the standard setup makes it possible to take artistic and documentary photos that you’d otherwise never be able to take. 

There are a few major benefits to taking your lights off your camera. The most significant advantage is that off-camera lights typically reduce the distance light travels through water. With only on-camera strobes, light travels from your camera rig to the subject and then back to your camera (where it’s captured). That’s a lot of water to go through, and it significantly affects both the color and the amount of light you get. With your lights mounted closer to your subject and off your camera, the light emitted only travels about half the distance. That means richer colors and a better lit picture. 

While Marcus and I shot pictures in the hold of the Thistlegorm, we took full advantage of these benefits. The room would have appeared dark and blue even with multiple bright lights mounted to my camera. While placing lights around the cargo hold was effective, this strategy has some significant disadvantages; the setup process takes a long time, and the entire time while you’re preparing you’re subject to the environment. You could stir up silt and cause bad visibility, you can lose a light between two trucks, or you can have someone come in and accidentally steal a strobe. Whatever the case, placing lights around a scene isn’t ideal for all situations, especially when you don’t have a lot of time. 

Inside of the SS Thistlegorm shipwreck with scuba diver. Photo by Kees Beemster Leverenz.
The SS Thistlegorm. Photo by Kees Beemster Leverenz.

Al Qamar Al Saudi 

Our best opportunity to try a different method came a few days after we dove the SS Thistlegorm: Marcus, Alex Adolfi, and I had the opportunity to dive the Al Qamar Al Saudi. The Al Qamar Al Saudi is a roll on/roll off ferry with a large car deck and room for 600-700 passengers. It’s a significantly newer ship than the SS Thistlegorm, having been completed in late 1970 and sunk in 1983. The car bay is also much larger than the cargo hold of the Thistlegorm. During our briefing before the dive, the Red Sea Explorers crew (our hosts) mentioned that the car bay was particularly spectacular, running nearly the entire length of the ship… but that it was a challenge to light. 

Challenge accepted. 

Fortunately for us, there’s significantly fewer divers visiting the Al Qamar Al Saudi than the SS Thistlegorm. Unfortunately for us, that’s because it rests in about 270 ft/83 m of water. The ferry is a deep, technical dive. Even with our rebreathers, a relatively short time on the bottom could mean hours of decompression to avoid injury. 

The wreck is enormous, and even with scooters just getting inside the car bay would take a lot of time. Once we got inside, we wouldn’t have the luxury of time to scout or stage lights. The space was much larger, so we decided to try a different technique: we’d have Alex and Marcus hold the lights and illuminate the inside of the ship as we went. While using divers to hold off-camera lights isn’t quite as reliable as staging a scene, it is much faster than the methodical process of placing lights around a space. 

Both Alex and Marcus were equipped with three lights each. The first light was the same that most GUE divers carry: a good quality primary light, used only for communicating within the team. The second light was a wide-beam video light mounted underneath their rebreathers, pointed back and slightly up, placed to make the divers more visible. Without this light, their dark drysuits and black fins would have been invisible against the darkness in the background of the hold. The final light was another video light that each diver held and pointed at anything they found interesting.

Inside of the wreck of the ferry Al Qamar Al Saudi. Photo by Kees Beemster Leverenz.
The Al Qamar Al Saudi. Photo by Kees Beemster Leverenz.

Although our dive was complicated by a scooter failure, we managed to get several decent shots from inside the Al Qamar Al Saudi during the few minutes we got to spend inside, thanks to the small array of diver-mounted off-camera lights. Marcus and Alex did an excellent job of lighting up the background of the car bay while my on-camera strobes lit up the foreground. With only on-camera lights, the depth of the space would have been hidden in the shadows, and if we had decided to place lights around the space, it’s unlikely we would have gotten any photos at all! As a side benefit, lighting a scene with video lights often makes the dive itself more fun for the divers involved, since the space is lit up everywhere, not just for the camera. 

Off Camera Lighting for Poor Visibility and the PB4Y Project

While artistic photos are a lot of fun, that’s not the only application of off-camera lighting. Support divers and bright off-camera lights have been essential for our 3D photogrammetry projects here in Seattle. 3D photogrammetry uses hundreds or thousands of images and specialized software to reconstruct a complete 3D model of a target, often a wreck. Each picture doesn’t need to be beautiful, but the subject does need to be well lit, so we can apply a lot of the same techniques we used in the Red Sea to our projects at home. 

Our most recent target was the PB4Y, a four-engine bomber from World War II that crashed on a training mission into our local Lake Washington. It’s been there since 1956, disturbed only by a US Navy recovery attempt just after it sank. While the airplane is in remarkable shape and the structure is nearly completely intact, the water that surrounds it is dark, cold, and murky; far from the clear blue water of the Red Sea. 

Lighting a scene is always challenging when visibility is bad. However, proper application of off-camera lighting can reduce the effect of poor visibility on your final picture. Most of the time, poor visibility is caused by silt or other small particles suspended in the water. Backscatter occurs when light bounces off particles floating in the water back towards the source of the light, causing hundreds or thousands of tiny points of light in your picture. If the source of the light is right next to the camera, as is the case with camera-mounted lights, backscatter can significantly reduce the quality of your images. 

By using diver-mounted lights (similar to how we lit the Al Qamar Al Saudi), backscatter can be nearly eliminated. Instead of the light bouncing off the particulate matter in the water towards the camera, it bounces back towards the support divers. The bulk of the light that is captured by your camera ends up being much “cleaner.” 

We’ve managed to model a few targets successfully so far in our dark, cold, and murky lake, and a project the size of the PB4Y has only been successful thanks to skilled lighting divers who illuminated the airplane from just the right angles. For this application, we find it’s best to have one, two, or sometimes even three divers actively moving around our target, lighting the way for the photographer. 

3D photogrammetry of the PB4Y plane wreck underwater.  By Kees Beemster Leverenz
3D photogrammetry of the PB4Y. By Kees Beemster Leverenz

For this project, each of our support divers carried a pair of 33,000 lumen BigBlue video lights. Since the two lights are quite heavy underwater, we connected them with a pair of float arms and rigged them with two bolt snaps. When they’re not in use, they can be easily stowed (in the same way as a stage bottle is attached). 

While we’ve been fortunate enough to have access to a lot of powerful lights, even a primary light can be effective for the purpose of cutting down backscatter or making an artistic photo pop off the screen, if you choose your subjects correctly and you’re willing to make a few mistakes along the way.

Additional Resources:

Are you interested in learning more about underwater documentation or photogrammetry? Explore GUE’s Documentation Diver or Photogrammetry Diver courses. 


Kees Beemster Leverenz is an enthusiastic diver and GUE instructor from Seattle, Washington, who enjoys getting in the water as often as possible. He has been deeply involved with GUE Seattle since it was founded in 2011. Currently, Kees is contributing to both local and global photogrammetry projects, as well as assisting with cave and wreck exploration projects whenever possible.


Community

Brits Brew Beer Booty

What do you get when you combine British divers’ proclivity for shipwreck exploration with their strong affinity for beer? A tasty treasure hunt on the “Wallachia” that resulted in swilling 126-year old reconstituted British beer. GUE Scotland’s detective chief inspector Andy Pilley recounts the tale.

Published

on

By

by Andy Pilley
Images courtesy of
A. Pilley

Header Image: GUE Scotland’s brewmeisters enjoying their brew (L to R) Top: Owen Flowers, Andy Pilley, Wayne Heelbeck. Middle: Steve Symington, A. Pilley, O. Flowers, Bottom: W. Heelbeck, Sergej Maciuk, S. Symington

“Give my people plenty of beer, good beer, and cheap beer, and you will have no revolution among them.”

Queen Victoria

I never thought when I started diving 10 years ago, that one day I would be able to sit down for a pint of beer with the team from GUE Scotland recreated from a brew that has been hidden under the waves for 126 years. Let me explain.

The Wallachia was a single screw cargo steamer that was owned by William Burrell & Son of Glasgow, and employed on regular trips between Glasgow and the West Indies. On 29th September, 1895 she left Queen’s Dock, Glasgow at 10am bound for Trinidad and Demerara. On board was a valuable general cargo including whisky, gin, beer, acids, glassware, and earthenware plus building materials and footwear. By 1pm that afternoon she had settled on the seabed of the Clyde Estuary after colliding with another ship in a fog bank, she was forgotten until 1977 when a local sub-aqua club rediscovered the wreck site.

The wreck of the Wallachia lies on an even keel in approximately 34 metres of water on a sandy seabed. The wreck itself is largely intact and has six holds in total, three forward and three aft. In the rearmost hold there are thousands of bottles of beer, some still inscribed with the name of the maker, McEwans of Glasgow. This is where myself and the team from GUE Scotland enter the story.

The Wreck of the Wallachia 

The Wallachia is one of the more accessible sites on the west coast of Scotland, where we carry out most of our diving. Depending on weather and tidal conditions, visibility on the wreck can be +10m/33 ft on a very good day or less than 2m/6 ft if there has been a lot of rain due to the amount of particulate in the water. Other elements to consider are the tide as this can vary in its intensity, as well as surrounding boat traffic. The wreck lies in close proximity to a ferry route and care must be taken not to dive when the ferry is closeby. However despite the challenges, the wreck is very rewarding and offers a diver plenty of places to explore and items to look at. 

The main point of interest for most has been the rearmost hold, where the bottles of whisky and beer were stored. The majority of the whisky was removed in the 1980’s however a few bottles can be found on occasion, depending where you look. What remains are thousands of bottles of beer, still with the corks and contents intact. Over the course of 2018 & 2019, the team at GUE Scotland dived on the wreck and recovered a number of bottles from the hold. 

After a chance discussion with a friend at dinner one night, I was given contact details for a company called Brewlab, which is based in Sunderland in the north east of England. Brewlab specialise in the provision of specialist brewing training, as well as laboratory services such as quality assurance, product development, chemical/microbiology testing as well as long term research options. I made contact with Keith Thomas, the Director of Brewlab, to discuss whether he would be interested in analysing the beer and investigating whether it could be recreated. Needless to say the proposal piqued his interest and arrangements were made for the bottles to be shipped to his lab.

Unbeknownst to me, the recovery of historical beers is rare, due to various sources of degradation/contamination which can affect any residual microbial cells and chemical components left in the beer that were used as part of the brewing process. So these samples are a valuable source of information on past brewing and microbiology. Over the course of 2019/2020, Keith and I kept in regular contact over the progress of the investigations and the full analysis of the beer has recently been published.

A Brewing Interest

Between 1850 and 1950, the application of scientific principles to brewing was becoming increasingly prevalent and microbiology was playing an increasingly important role. A pertinent issue in brewing microbiology around 1900 was the application of pure Saccharomyces yeast cultures developed by Hansen at the Carlsberg laboratory in 1888. These were readily adopted by continental breweries as providing more controlled production and purer beers. Application to UK brewing was, however, less positively received, in part because of the belief that British beers possessed particular flavours arising from mixed yeast cultures and, specifically, the involvement of Brettanomyces species. This was especially believed to be essential for the character of ‘stock’ ales which were matured for extended periods.

While a number of breweries did try pure culture yeasts, UK brewing was resistant to change and, with the intervention of World War I, retained its indigenous yeast cultures. Since the 1940’s a more biotechnological approach to fermentation demonstrated the value of pure culture and was progressively applied to the larger breweries developing at that time. 

During the formative period of brewery microbiology after Pasteur, brewing yeast were identified as Saccharomyces species based on morphological features of shape, filamentous propensity and spore characteristics. Non brewing, ‘wild’ yeast was recognised and termed ‘Torula’ if non-sporulating. Of these Brettanomyces strains were identified as contributing important character to stock ales. It is also clear from brewing texts that bacteria were recognised as spoilage organisms in beer, as had been initially demonstrated by Pasteur in 1863. These species were mostly categorised as bacilli and typically portrayed as rods and associated with sarcina sickness – generally producing sourness. Some studies, nevertheless, identified lactic acid bacteria as indigenous components of standard beers.

Contemporary breweries are increasingly interested in using novel microbiology, either unconventional yeast strains or mixes of species and strains for sour and natural products. Identifying the specific strains and species of yeast and bacteria present in Victorian and Edwardian beers is directly relevant to this and has particular value if cultures of authentic microorganisms can be retrieved. Reports of retrieved historic brewery microbiology are limited but hold interesting promise for identifying novel microorganisms.

The specific parameters of the analysis are contained in a published research paper, Preliminary microbiological and chemical analysis of two historical stock ales from Victorian and Edwardian brewing.”

As I mentioned, the primary objective of the analysis was to confirm whether detail could be provided on the original brewing ingredients and the fermentation microbiology. The analysis confirmed the use of Brettanomyces/Dekkera bruxellensis and Debaryomyces hansenii, which are brewing and fermentation yeasts respectively. The presence of Debaryomyces is interesting as this genus has not been noted as a historic feature of historic brewing, but has been identified in spontaneous fermentations, for example in Belgian lambic beers. Although the strain was reported to the brewing industry in 1906, it has not featured as a major contributor to beer fermentations since.



The analysis has also provided relevant information of the beer character and has confirmed that the beer recovered from the Wallachia was a stout, close to style expectations of the time and had an alcohol content of c. 7.5%. The colour gravity was high, resulting in a much darker beer however a much lower level of bitterness. Again this was typical style of the time and differs from other modern stouts.

More interestingly is the presence of various types of bacteria, which will likely have been picked up during the brewing process. The table below lists these for reference. Needless to say, historic brewing was not a sterile process in comparison to modern methods!

Bacillus licheniformisPlant and soil bacterium
Finegoldia magnaCommensal skin bacterium
Fusobacterium sp.Possible pathogenic bacterium
Kocuria roseaPossible urinary tract pathogen
Mogibacterium pumilumPossible oral cavity bacterium
Shigella sonneiEnteric pathogen
Staphylococcus epidermidisCommensal skin bacterium
Stenotrophomonas maltophiliaSoil bacterium
Varibaculum cambriensePossible pathogenic bacterium

Table 1: The bacteria found in the Wallachia beer bottles

Due to the relatively stable conditions on the wreck, being in near darkness and at a relatively cold temperature (between 6º–14ºC/43º-57ºF depending on the time of year), the live yeast structures within the beer were protected from sources of stress and allowed them to survive over the past 126 years. Luckily, Keith was able to extract these samples and begin to recultivate the yeast, specifically the Debaryomyces, with the hope of being able to rebrew the beer.

Cheers Mates

Just before Christmas, I finally received word from Keith that he had completed a trial brew and seven bottles of the brew were on their way to me. A few excitement laden days later and a nondescript box arrived at my office with the beer inside. I called the guys on our Facebook group chat to show them the case and got each bottle packaged up and sent out to them. 

A few days later, once everyone had received their sample we got together again to try the samples. There was an air of excitement after the two years it had taken us to get to this point, the most anticipated pint ever! I’m no expert in the flavour profiles of beer so you will have to forgive me for my relatively basic analysis. In summary, I got flavours of coffee and chocolate and there was a relatively low level of carbonation, which made it very drinkable. The rest of the team got similar flavours, the only complaint being there wasn’t more to try!

There will of course be slight differences in flavour since we don’t normally add the bacteria listed above as ingredients. However, the recipe we have is as close as we can make it to the original stock version.

The next steps for the project are to carry out further investigation on the characteristics of the Debaryomyces yeast strain in order to determine their suitability for fermentation and potential use in future brewing production. We are making approaches to various commercial breweries in order to discuss future commercialisation of the recipe and produce the brew on large scale. With the story behind the original recipe, we’re hopeful that the provenance would be a key selling point to consumers. It is my hope that the recovery of these samples will open up new possibilities for different types of beers to be developed, and offer something different for beer enthusiasts to try.

I have also found out that there are other types of beer to be found on the wreck, specifically an IPA style. Once we’re allowed to begin diving again, I am hoping to return to the Wallachia and recover some of these bottles so we can carry out the same analysis and keep the project moving forward.

In the mean-time, cheers!

Additional Resources:

The Brewlab Podcast, Episode 2 (March 30, 2021): Lost Beers Recreated from Shipwreck Bottles

GUE Scotland vlog -Episode 1


Andy Pilley is a Chartered Surveyor, team member of GUE Scotland, passionate wreck & cave diver and Ghost Fishing UK team diver. Andy started diving with the Scottish Sub-Aqua club in 2011 and began diving with GUE in 2018. Andy dives on the east and west coasts of Scotland where there is a rich maritime history and an abundance of wrecks to be explored. He has a passion for project diving and is developing objectives for a number of sites with the GUE Scotland team. He hopes to assist on the Mars Project and with the WKPP in the future.

Continue Reading

Thank You to Our Sponsors

Subscribe

Education, Conservation, and Exploration articles for the diving obsessed. Subscribe to our monthly blog and get our latest stories and content delivered to your inbox every Thursday.

Latest Features