Lighting for underwater photography has its unique set of challenges but the rewards can be beautiful. And when you're lighting underwater macro photography, it's all the more challenging...and rewarding!
Underwater macro photography can be one of the most rewarding forms of capturing images of colorful forms, funny faces, and strange creatures in the ocean environment. Even the latest rugged, submergable compact digital cameras that can focus close and have their own internal flash can bring some interesting imagery and great memories from your dive trip. However, compact digital cameras may only be a tease to all that can be done with macro photography. The next and one of the most important ways to begin to improve your pictures is to consider underwater lighting for your tiny submerged subjects.
Let me remind you of some basic elements that come into play with any underwater photography:
- Unless you are in very shallow water and there is very bright sunshine with clear visibility, your images will lack the vibrant colors that actually exist in many macro subjects. Water absorbs spectrums of color—starting with red.
- An internal strobe can produce ugly backscatter since particulate of some form usually floats in most oceans.
- Flash helps increase shutter speed and depth of field
How Many Strobes Should I use?
There can be several factors that determine how you choose the number of strobes. Many divers only want to come back with fond memories of their trip and not worry about carrying so much gear. Others, like myself, are completely obsessed and carry almost every conceivable gadget known to man. We are the true geeks of the underwater world.
The types of strobes available are abundant. Even system compact digital cameras come with a variety of options. But the most important thing is to have at least one dedicated strobe that can be positioned many ways. Let’s talk about the power of the strobe and light falloff. This is determined by the power of the strobe and the distance from the subject. The rules for falloff come with a formula: Moving away from a subject will reduce the power by ¼ for each 1 – 2 feet.
Single strobe users can produce quality images and the best way to become used to your strobe, its strength and the direction of the light, is to start by placing the strobe directly above your lens and front-light the subject.
Strobe positioned directly above and behind the front of the lens.
Single strobe front lighting the subject. f/22 at 1/100th second.
Lighting from the side can add texture to an image. It can also add harsh shadows to the subject.
Note that certain lighting positions can make the backscatter more prominent than others. f/22 at 1/100th second.
Many photographers like to mimic the sun by lighting from the top and for single strobe users, this is an acceptable way to light the subject.
Single strobe top lighting. Note shadow directly under the starfish arm to the left of the image. f/22 at 1/100th second.
Dual Strobe Use: Steering You To The Right Light
I prefer using two strobes for most of my underwater photography. I have much more control and increased power, which allows me to use the smallest aperture for the best depth of field. How to position your strobes can be a fun experiment to see how it affects the image.
There is the tried-and-true “ten and two” strobe positioning. Remember when you learned how to drive the instructor said to place your hands on the steering wheel in the 10PM position for the left hand and the 2PM position for the right? This is an excellent starting point and will generally result in a pleasing image.
Strobe positions in the “10 and 2” position.
Tasseled scorpionfish. Strobes in the “10 and 2” position. f/32 at 1/160th second with full strobe power and 100mm lens.
I do like making adjustments to the strobe position depending on where and how where my subject is located. Many times, the face of the subject and the strobes placed above the subject can produce a harsh shadow below. The best thing is to move one of the strobes to light underneath the subject. In the next photo, my strobes were place in the “10 and 4” position.
Lizardfish shot at f/32 at 1/100th second, 100mm lens. Note that by moving my strobe, I was able to light under the jaw of the fish.
The “10 and 4” position to light under a subject. The can be changed to “2 and 8” depending on which way your subject is facing.
Diffusing the Light
There are times when you want a softer, more even light to “wash” across your subject. There are two ways you can do this. One is to add diffusers to your strobes. I keep my diffusers tethered to the strobe so they are available when needed.
Using fishing line and swivels, I can easily place or remove my diffusers. It eliminates the chance of losing one on a dive.
The one consideration to make when using diffusers is that you will lose at least a full stop of light. It helps to experiment a bit and check your image/histogram to see if you need to move the strobes closer/ farther from the subject, increase the power of the strobe or change your camera settings.
100mm lens, f/18, 1/100th second. I used the diffusers on my strobes because the squid can easily be over-exposed. I also wanted a softer “wash” of light on the subject.
You can also position your strobes so just the outer edges of the light gently cover the subject. This creates a softer look but will require more strobe power.
The image below can demonstrate what happens when only one strobe is used from the side. I needed to have the tiny blenny highlighted but the shadow that was created was not appealing. When I brought the second strobe in to light the back side of the blenny, it created a more balanced image.
Blenny exposed at f/22 at 1/60th second, 100mm lens and one strobe.
Same blenny exposed with dual strobes. F/25 at 1/100 second, 100mm lens.
Dual strobes positioned for side-lighting on a close focus subject.
Having the ability to move strobes around can mean the difference between properly lighting a subject, or not. In the samples below, I had a wonderful small lobster peering out of its den. The problem is that I had a seafan to the left of the lobster, which created a terrible shadow. By repositioning my strobes, I was able to get the correct lighting/exposure.
Small lobster in Palau, Micronesia. F/32 at 1/160th second, 100mm macro lens with full power on both strobes.
This can be a very creative way to photograph marine life – especially those with interesting shapes. This image was graciously provided to me for this section as it is the perfect example of this technique. It may require removing a strobe from the mount to position it directly behind the subject. It’s also handy to have help from your dive buddy!
Wonderful backlit image of a harlequin ghost pipefish by Jason Heller.
Let’s recap some of the strobe positions. There are many ways you can make your macro image just a little more compelling. Experiment – play with strobe power – have fun!
- By deviating from the “traditional” front lighting positioning, you will open up a world of creative opportunity. Some ideas include.
- Sidelighting: creates texture and dimension, emphasizes certain features of the subject
- Toplighting: creates the effect of uni-directional lighting, prevents the illumination of parts of the foreground that you may wish to leave unlit.
- Backlighting: creates a dramatic and unique effect of glowing edges around a silhouetted subject, can make translucent subjects appear to glow from within.