
So you just finished watching a great white shark feeding video and thought, “Wouldn’t it be awesome to be in the water with a camera to film this feast?” I'm right there with you, which is why today we’ll be diving into the world of underwater video creation, from the gear you’d need, to tips for getting the perfect action shot.
Before we get into it, I’d like to leave a little disclaimer: while venturing out into the vast and expansive deep blue is a riveting adventure, please practice caution and, if you’re not experienced in underwater filming, be sure to have a trained professional nearby. Filming is hard enough on land―be safe, be smart.
Not All Light Waves Are Equal, Especially Underwater
Cinematography, photography, videography, and all the other camera-related -graphies all boil down to how light travels through the air and hits a sensor. After all, the images that populate our memory cards are a direct result of the visual information that is transmitted by light rays. The camera is simply a tool to collect that information.
Unfortunately, when you submerge in deep water, a lot of the visual information that makes up a great image gets lost―mainly the colors as the light filters down from the surface. The deeper one goes, the less prevalent colors become. However, if you’ve ever gone swimming at any sort of depth, you’d probably have noticed that this color loss isn’t exactly uniform and, rather, knocks individual colors out the deeper you go. Colors will gradually fade the deeper you go in this order; red, orange, yellow, green, and finally, ending with blue. In fact, red starts giving out at depths of only 10-15 feet, while blue persists all the way up to depths of more than 300 feet!
The reason for this is each one of these colors carries unique wavelengths and energy values that react differently upon entering water. Of these colors, red has the largest wavelength and lowest energy level, and conversely, blue has the shortest wavelength and highest energy level. While I'm no physicist, the color loss is determined by the energy and wavelength values of each color in the light spectrum. The greater the energy and shorter the wavelength, the deeper it can travel and the better it is at not getting absorbed by the water around it. As I said, I'm no physicist, but if you’re going to be filming underwater, you need some sort of understanding as to why the colors fade from everything around you the deeper you plunge into darkness.
Manual White Balance All Day, Every Day
Now, as evidenced in our mini-physics class, capturing color underwater is a bit more precarious than capturing it up above. This is why it is critical to know how to white-balance your camera for underwater shoots, because this will be the best way to maintain as much color information as possible when working solely with the ambient lighting underwater.
First things first―forget about auto white balance. It doesn’t exist, at least not for underwater shooting. Having your camera rely on its auto white balance function is one of the most surefire methods to ruin a dive shoot. Auto white balance is basically the camera guessing what white is and correcting for it on the fly; however, that function gets thrown for quite the ringer when you bring your camera into the water.
With water inherently absorbing and removing color as one goes deeper, a substantial amount of information that a camera would normally use to correct for white is no longer available. To make sure you get the best of the colors that are present in the scene, always set your white balance manually. In fact, get ready to make it second nature to adjust your white balance about every 10–15 feet you change depth. While your safety during underwater expeditions certainly takes top priority, staying on top of your white balance might be a solid second. It's never any fun to come back from an underwater excursion just to see that all your footage is completely blue. White balance is key!
While its totally viable, simply eyeballing your white balance underwater isn’t the easiest task, especially if your monitor is small or the water is foggy. I recommend utilizing a white card or gray card; it really removes a good amount of the guesswork, especially if you're moving around a lot. I prefer the gray card because it's easier to set exposure for it underwater, since an improper exposure value can skew white-balance values. The Vello White Balance Card Set is a solid option, especially since it comes with a lanyard, which will keep it from drifting away from you; it's a nice bonus that it includes a black and white card alongside the standard 18% gray card.
Don’t Drown Your Camera
It goes without saying that your camera is going to need some protection from the big blue, so it's time to get fitted with an Underwater Housing. I’ll come right out and say it: if you’re planning on going underwater even somewhat regularly, this is not a piece of equipment you should skimp on, especially if you plan on deep diving. I’d recommend avoiding a “one-size-fits-all” housing solution. These will probably render your camera buttons useless, since varying camera manufacturers don’t share the same button layouts. You’d just be floating around with a waterproof but inaccessible camera. Most current mainstream cameras will have custom form-fitted options available. I shoot with a Sony a7S III and, for reference, I prefer the custom-designed Aquatica Underwater housing for it.
This housing is a precision-machined hunk of anodized aluminum alloy with stainless-steel control shafts and buttons. It makes things easy to venture out confidently and film for as long as needed; if there's no user error (for instance, not sealing this properly prior to a dive), the camera is more than protected from the wet. Aluminum housings are the best option when considering an underwater housing for your camera since they are, by far, the king when it comes to durability and watertightness.
Aquatica offers an extensive list of aluminum housings for a wide variety of cameras, if you’re looking to find a proper fitting for your rig. They do come at a high cost, however, and you may have noted that the housing is basically the same price of an a7S III. The cost for peace of mind is rarely inexpensive―this is not to say that there aren’t viable economical options that are readily available at B&H. Take, for instance, the underwater housings offered by Ikelite, which are constructed from Acrylonitrile Butadiene Styrene Polycarbonate or ABS-PC for short. These housings can reach depths of 200 feet while being half the price of traditional aluminum housings. Both housing types are excellent―however, if you’re planning on going on extreme dive trips that exceed depths of 200 feet, I certainly would recommend the aluminum solution.
Float Arms
Now that you have your underwater housing ready to go, remember you’re going to need to be able to push it effortlessly through the water without it dragging you down, tiring you out, or straight up sinking to the ocean floor. This is where buoyancy becomes important, and float arms help. Float arms are designed to increase your rig’s buoyancy. This is going to take some trial and effort since everyone's rigs will all have varying degrees of positive or negative buoyancy.
The more negative a rig is, the more floats you may need and, on the flip side, the more positive it is, the more you’re going to have to weigh it down. Regardless, in most cases, you will need floats. Floats come in a variety of sizes and are rated in terms of how many grams or ounces of buoyancy they will add to your rig. Ideally, you’re going to want to achieve neutral buoyancy, at which point your camera neither sinks nor rises when you let go of it, and instead floats weightlessly in front of you. You’ll have to undergo some trial and error to find what works for your particular gear. A good start is by weighing your entire setup and utilizing a combination of arms that would effectively neutralize the weight of your rig in the water. Unfortunately, it can be quite tedious to find a truly neutral setup but, with some determination, you’ll be able to figure it out.
Light It Up!
Things can get dark underwater, and quickly. A strong underwater light can greatly elevate your underwater footage because the added light will reintroduce color to the scene! That’s right―remember how we talked about color dissipating the deeper you go? That was in reference to the ambient light provided by our friend the sun. A strong external light can help bring color to you. The rule of thumb is the stronger, the better, since a higher lumen value will allow you to light your scene better and reintroduce color. Something like the Bigblue VL65000P would be an excellent light to bring along, thanks to its whopping 65,000 peak lumen output. The great thing about a strong light like this is that you can always decrease the output level if you don’t need that much light, but the power is always there for when you need it. Other great options that feature much friendlier prices are the SeaLife Sea Dragon Series and Kraken Sports Hydra. While these lights aren’t as powerful as the Bigblue, they will still light up your scene plenty―you’ll just need to swim closer to your subject, which is considered good practice in underwater filming in the first place. The closer your subject is to your lens, the less water there is between you, equating to less light absorption by the surrounding water and less particle scatter.
Underwater Camera Lanyards
Now that you’re set up, you’re going to need a way to keep your rig from floating away from you. After all, you’ve probably invested in it, and it’d be a shame if a rouge slobbering catfish snagged your rig from you (yes that’s the real name of that breed of catfish, Brachyplatystoma platynemum, if you want to get zoological). A simple underwater lanyard will solve most of your thieving catfish problems.
Get to Swimmin’
Underwater videography is no simple activity, and there is much more to it than this article covers. It was my hope to cover some of the very basics of what you might need for such a project.
Please feel free to continue your underwater education with Learn to Light Underwater, Keep the Sea at Bay: Underwater Housings for DSLR and Mirrorless Cameras, & Getting Started in Underwater Imaging. If you’re new to the world of underwater filmmaking, what are you most excited to capture? Let us know, below!
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