Lighting up the Darkness Underwater
First Things First
Most underwater exploration takes place during the day in open water. The underwater photographer can create three-dimensional looking images by carefully balancing the ambient light of the background with the artificial light that is used to illuminate the subject. The only time the underwater explorer will be in total darkness is on night dives or when inside an overhead environment such as a shipwreck or cave.
During night dives, we are still in open water; even new divers can enjoy this experience. Divers should still carry a primary light source and two back-ups. Unlike when in overhead environments, in case of an emergency the diver could still go directly to the surface. This allows for a simple dive and bailout plan.
As far as lighting for photography, there aren't any walls for the light to bounce off of, so it does not pay to light up the background. During night dives, it is best to use one or two strobes to light up your subject and let your background go black. Since there isn't any available light, you may as well use a fast shutter speed to stop movement of your subject and reduce camera shake. Use side lighting to bring out texture and to separate your subject from the dark background. Why bother with all this? Because some really interesting marine life is active at night. This includes some very small creatures. Shooting macro and planning for animal behavior images can be rewarding and worth the effort.
If we are going to do photography in an overhead environment, remember safety always comes first, imaging second. Cave diving and wreck penetration are real specialties. In an emergency the diver CAN NOT go directly to the surface. First you have to reach open water in order to surface. For this reason you need special gear, rigging and training. Diving in overhead environments has to be taken seriously. It is very important for you to be comfortable in a cave or wreck before bringing in your camera rig. Also make sure you have extensive photo experience in open-water before wandering into a cave or wreck with your camera. Know your gear with your eyes closed; remember you might be working in total darkness. It is way too easy to forget the rules while concentrating on creating an image. Ignoring the rules of overhead environment diving could really ruin your day and every one of your days after that.
Nevertheless, cave and other overhead environment training has great rewards. You will learn to be a better diver in all situations. Entering a cave or shipwreck really is going where few humans have gone before. Being inside some caves, feels like you have left the planet earth and you are in a remarkable other world. The only thing more exciting then being there is returning with stunning images of these remarkable places.
So What Now?
Ok, now we have our full cave certification, have 50 cave dives and 40 dives inside our favorite wreck. Now let's take some photos. First we need to produce sharp images. Today's modern cameras have allowed photographers to get lazy and depend on auto focus. These systems really are very good but require some light and subject contrast in order to work. Inside a cave or shipwreck, however, there is no light. Therefore, many cave photographers still use manual zone focus techniques. To do this, we need to preset the lens and use our depth of field in order to keep the image sharp within a certain distance range. Underwater we want to use ultra wide-angle lenses anyway, and they have a deep depth of field range. Also, we want to work as close to our subject as possible, so we don't have to hold focus past two feet. Most modern lenses no longer have a depth of field scale. Instead there is an online Depth of Field Table, which is very helpful for figuring out pre-focus settings (go to http://www.dofmaster.com/doftable.html). For example, if you are using the Olympus 7-14mm zoom, you would first set the lens to 7mm, the focus to one-foot and the f-stop to F8. Use tape to prevent these settings from slipping. With these settings, your image will be sharp from 6.9" to 3'8.3". All you have to do is approach the subject and push the shutter release when you are within this distance range.
Another technique is to use a strong focus light to allow the auto focus to work. You can have a team member hold a primary light on your subject in order for your camera to focus. You can also attach a strong back-up light to your camera rig. For this purpose, I have tried lights manufactured by Sartek, Diverite, Fantasea, Intova, and Solus. All have worked to some degree. Remember to set your shutter speed so the focus light will not affect your image. Since you are shooting in the absence of available light, a slow shutter speed will not help you anyway.
Staying in the Cavern Zone
When you first get started in cave photography, you will be more successful in the cavern zone. The cavern zone is the area of the cave where there is still natural light from outside. First of all, the dive is less demanding. Next, you can use the ambient light to your advantage. You could use one or two strobes to light your subject. Then use the ambient light for the background just like you do in open water. As with most underwater photography, you want to have your camera set on manual exposure control. You should be in the cave area with the open water behind your subject. With all underwater photography, use the widest lens possible and get as close to your subject as you can. Never be more then two feet away from your subject. The closer you are, the better your images are going to be.
Set your shutter speed for the ambient light in the open-water area. Underexpose your ambient light about 1/3rd to 1 stop. In order to contrast with the dark surroundings of the cave, you might want a lighter background than you would use in the ocean. You still want to make sure you don't burn out the background. Position your strobes on your subject and control strobe exposure with your F-stop or power control. Remember changing your shutter speed will affect your ambient light exposure (background). Changing your f-stop will affect your ambient light and strobe exposure (background and subject). Changing the power of your strobe will only affect your subject. That is why strobes with power control dials are best for all underwater photography.
Shooting in the cavern zone should make some interesting images. You get really nice patterns in the background. Entering a wreck and staying close to the entrance, you can use the same techniques. This will keep both the dive plan and the photography simple, and be much safer than a deep penetration.
Shooting in Total Darkness
Once we enter the cave or turn away from the cavern zone, we are in a completely black environment. We need to bring all our lighting with us. Basically it is akin to lighting a room just like an architectural photographer does in a house or office building. This kind of photography is difficult enough, but we have the extra challenge of total darkness and being underwater!
In order to create dimension and show the cave or wreck interior we have to add a backlight. We are trying to create the same affect we use ambient light for in open water, but now we have to bring the light with us. The Ikelite DS-200, DS-160, DS-125, or DS-51 work best for the backlight because these strobes are capable of accepting a long extension cord . This will allow you to position the external slave trigger on the model so that it will fire when it detects the flash of the camera's strobes.
Here's How to Rig Your Model
Use a bungee cord to attach the strobe to the model's tanks. The strobe should be facing towards the diver's fins. It's best to put in a wedge so the strobe is pointing up a little. Run the slave to the front of the diver and attach to a D-Ring. The Ikelite manual controller is very good for this purpose. Since the controller allows you to change the strobe power from the controller, you don't have to swim behind the subject for adjustment.
Have the diver face you, with the attached strobe facing away from the camera towards the back of the room. When the strobes on your camera rig fire, the slave will fire the backlight strobe. It is important that the backlight does not burn out the background. Depending how far away the back wall is, you might not need a lot of power, but you do need a wide soft beam of light for a more natural look. Doing this creates a three-dimensional look to the photograph and allows you to see detail in the background. Most cave photographs are better with a diver in the photo to show scale. Your model diver should have proper equipment rigging for the environment that you are shooting in. The model should also be carrying a primary light. You could use your subject's light to create an interesting composition element to your photograph. This is the same inside a wreck, but don't forget to also create a still-life of the ship's machinery and other artifacts.
This is very technical photography and requires patience, communication and planning with your subject and all the other team members. One of the advantages of shooting digital is seeing the results instantly so you can then make adjustments. So take your camera, a whole gaggle of strobes and go jump in a flooded hole in the ground! Experiment, have fun and dive safely!
|Photo by Polina Reznikov
Larry Cohen has worked as a studio and location photographer since the late 70's. His clients included Baccarat Crystal, Fuji, Kodak, Sony, General Electric, Time Warner. His underwater photos have appeared in such publications as Sport Diver, Immersed Magazine, Sub Aqua Journal, Alert Diver and Northeast Dive News, where he is now writing a monthly column. His photos have also appeared in books such as National Audubon Society Field Guide to Tropical Marine Fishes. In order to extend bottom time and to get closer to marine life he now dives with a Closed Circuit Rebreather. Larry is a founding member of the New York Underwater Photo Society. He is a past president and active member of The NYC Sea Gypsies dive club and is on the committee of Oceanblue Divers dive club in Manhattan. At B&H Photo Larry is a technical writer.
Visit Larry's site at www.liquidimagesuw.com
Equipment used: Olympus E410 and E330 (Similar- Olympus E520), Olympus 7-14mm Lens, Olympus PT-EO3 Housing, Sea & Sea YS110 Strobes, Olympus FL36 Flash and the Olympus Strobe housing PFL-E01.
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