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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!

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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.


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Our Most Read Stories of 2020

Dive into our most read stories of 2020. Can cameras kill? What about those peculiar GUE rebreathers? Gradient factors anyone? Was it a world record dive? Find out.

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Header photo by Sean Romanowski

Greetings Tekkies,

This December marks the second full year of publishing InDepth, and what a crazy year it’s been. With the pandemic still raging throughout most of the world, it has been a most challenging year for the diving industry, as I’m sure you’re aware. I would like to take this opportunity to thank you, our readers for your continuing interest and support, and also thank our thoughtful contributors who make the blog possible.

Over the last year, we published nearly 100 InDepth stories covering the latest developments in exploration, technology, training, conservation, diving science & medicine, image making and technical diving culture. We also added select translations into Chinese, Italian, and Spanish . In doing so, I believe that we have grown our coverage in terms of breadth, depth and sophistication. Call it, a geeky labor of love!

In addition, we’ve added some depth-full sponsors to the mix, that have made it possible to grow and sustain InDepth. Our special thanks to DAN Europe, Dive Rite, Divesoft, Fourth Element, Halcyon, The Human Diver, and Shearwater Research. May your brands continue to flourish! 

Similar to 2019, we celebrate the coming new year with our Most Read Stories from 2020/2019. If you like what you read, please SUBSCRIBE, it’s free! That will ensure you’ll get our latest stories and content delivered to your inbox. Here’s to a hopefully wet and most excellent 2021!

—Michael Menduno/M2


Photo by Natalie Gibb

1. Cameras Kill Cavers Again 

Cave explorer, photographer and instructor Natalie L Gibb wants to make “taking pictures” the sixth rule accident analysis. How can toting a camera underground get you into trouble? Take a breath, clip off your camera, and say cheese, Gibb will explain.

Photo by Ortwin Khan

2. The Thinking Behind GUEs Closed Circuit Rebreather Configuration 

GUE is known for taking its own holistic approach to gear configuration. Here GUE board member and Instructor Trainer Richard Lundgren explains the reasoning behind its unique closed-circuit rebreather configuration. It’s all about the gas!

Photo by Joakim Hjelm.

3. Gradient Factors in a Post Deep Stop World 

World-recognized decompression physiologist and cave explorer David Doolette explains the new evidence-based findings on “deep stops,” and shares how and why he sets his own gradient factors. His recommendations may give you pause to stop (shallower).

Image courtesy of DeeperBlue.com.

4. Fact or Fiction: Revisiting the Guinness World Record Dive 

Newly released information calls into question the validity of former Egyptian Army Colonel and instructor trainer Ahmed Gabr’s 2014 world record scuba dive to 332 m/1,090 ft in the Red Sea. InDepth editor-in-chief Michael Menduno reports on what we’ve learned, why this information is coming out now, and what it all may mean.

Photo courtesy of Sea Shepherd.

5. Can We Save Our Planet? What About Ourselves? Interview With Sea Shepherd founder Paul Watson.

Managing editor Amanda White poses the BIG questions to environmental activist Captain Paul Watson, founder of Sea Shepherd Conservation Society and the architect behind its strategy of aggressive non-violence. His answers may surprise you—and even bring you to tears. What motivates the 70-year Environmental Hero of the 20th Century to keep up the fight despite widespread ignorance, apathy and greed? Find out.

Photo by Derk Remmers.

6. Isobaric Counter Diffusion in the Real World 

Isobaric counterdiffusion is one of those geeky, esoteric subjects that some tech programs deem of minor relevance, while others regard it as a distinct operational concern. Divers Alert Network’s Reilly Fogarty examines the physiological underpinnings of ICD, some of the key research behind it, and discusses its application to tech diving.

Photo courtesy of Michal Guba.

7. Deepest Freshwater Flooded Abyss in the World 

The efforts to explore and map Hranice Abyss, located in Hranice (Přerov District) in the Czech Republic span more a century. Currently, the monstrous chasm is known to reach 384 m/1260 ft deep. Explorer and member of the Czech Speleological Society Michal Guba has the deets.

Photo by Rich Denmark.

8. Urination Management Considerations for Women Technical Divers

Tech diver and doctoral student, Payal Razdan, offers an in-depth review of the options available to women tech divers for handling the call of nature.

Photo by Kirill Egorov.

9. Situational Awareness and Decision Making In Diving

Situational awareness is critical to diving safety, right? But how much of your mental capacity should be devoted to situational monitoring, e.g., How deep am I? How much gas do I have? Where is my buddy? Where is my boat? More importantly, how does one develop that capacity? Here GUE Instructor Trainer Guy Shockey, who is also a human factors or non-technical skills instructor, explores the nature and importance of situational awareness, and what you can do to up your game.

10. Examining Early Technical Diving Deaths

The early days of technical diving were marred by an alarming number of fatalities that threatened the viability of this emerging form of diving. Here InDepth editor-in-chief Michael Menduno presents the original accident analyses of 44 incidents that resulted in 39 fatalities and 12 injuries, as reported in aquaCORPS Journal and technicalDIVER in the early to mid 1990s.

11. A Voice In The Wilderness

Just when you thought you’ve seen it all, along comes underground picture-maker SJ Alice Bennett, who is shedding new light on the dark, moody, twisting karst passageways that form what explorer Jill Heinerth calls “the veins of Mother Earth.” If you’re ready for a new perspective on the ‘doing of cave diving,’ switch on your primary and dive right in.


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