BE THE CHAMP! - Off-camera strobes
'The greatest benefit of off-camera strobes is the mood that this style of lighting gives to images'
“TODAY, CREATIVE DARING is no longer an act of courage, but a basic requirement if you want your work to be noticed and your stories heard”.
These are not my words, but come from nature photographer Niall Benvie’s excellent book Outdoor Photography Master Class. There is not a single word on underwater photography in it, but if you want your creative juices stimulated it is a highly recommended read.
Niall’s observation is that with the world awash with quality images, a great subject and technical excellence is no longer enough to be the champ. Creativity in photography has never been more important.
Remote strobe lighting is not a new technique under water. The art has been perfected for years by the leading cave photographers, such as the late Wes Skiles and Jill Heinerth. But only recently has the technique become popular on recreational dives, offering significant potential to inject our pictures with some of that elusive creative flare.
Being a niche technique, you will be hard-pressed to find information on how to do it in any books on underwater photography.
And if you jump in unprepared, I can guarantee that a remote strobe will be incredibly frustrating. So this month’s column is a little more technical as I share the whys, hows and kit for off-camera strobe photography under water.
WHY OFF-CAMERA? Remote lighting certainly endows our photos with an innovative sparkle. But just as importantly, it provides useful lighting solutions. In low-visibility conditions, off-camera strobes can provide illumination free from backscatter, because the overlap between the strobe and lens is very small.
The technique can also boost contrast, particularly for more distant subjects in the frame, especially when used as backlighting.
Probably the greatest benefit of off-camera strobes is the mood that this style of lighting gives to images. Most underwater images require strobes, which can normally light only the front of our image.
When we get the strobes away from the camera, suddenly we are able to add light to a scene in a different way, as for example when we place the subject in the middle ground of the image, framed with a dark foreground.
I have found this lighting style particularly suitable for capturing the atmosphere of wreck interiors and reef caverns.
As with any craft, photography needs the right tools for the job. If you dive in darker places, such as inside wrecks or in British conditions, you can dip your toe into remote strobe photography by using a powerful, wide-beam torch, like >800 lumen LED focus/video lights.
In bright conditions the sun will overwhelm a torch, but in suitably gloomy conditions this is cheaper and easier to use than a remote strobe. You can see exactly what the light is doing and there are no triggering issues.
Ultimately a strobe is more powerful and controllable, especially relative to ambient light. To accurately position and aim a remote strobe I use a plastic Gorillapod fitted with a mounting ball to which to clamp the strobe. This will be more stable if a small diving weight is hung between the legs.
At a push you can try off-camera strobes by simply resting your strobe on the ground, but this is very limiting.
If we are working with a model, or have an obedient buddy, we can consider asking that diver to hold the strobe, or mount it to his or her cylinder (on the far side from where we are shooting) pointing at the background (wall of cave, bulkhead of wreck etc).
When fired this will leave the model silhouetted against the background, although we can choose to light him or her up with our on-camera strobes too.
SETTING UP off-camera strobe shots is time- and attention-consuming. Plan these shots with your buddy, making that person the focus of your dive. Practise these techniques in shallow, benign conditions.
On land, if you wanted to place a strobe behind a chair opposite you, you would put your camera down, walk around the chair, place the strobe and walk back. And then go back and forth a few times adjusting the power and angle of the light.
It's the same under water, but all of these stages take much, much longer. And we have the additional problem of kicking up backscatter!
It is crucial to make sure that your strobe is triggering correctly. You must check that it's showing up in the picture, and not flashing out of sync.
Strobe triggers easily get confused by pre-flashes, and you want to fix this pre-dive. So make sure your camera, on-camera strobe and off-camera strobe are all set on manual with no pre-flashes, and that the off-camera strobe flash appears in your photos before you try it under water.
Once diving, spend time searching for a good location for the shot. Pictures through doorways on wrecks or archways in caverns often work well.
Place the strobe through the doorway, hidden round to one side, with the cable stretched back to the door with just the trigger sensor visible. Turn your on-camera strobe to minimum power (if using two, turn one off). Turn your off-camera strobe to a high power.
Shoot and adjust the aperture until the exposure from the off-camera strobe is correct. This might already be job done, although you may want to adjust the shutter speed to either block out or let in any ambient light.
If the on-camera strobe is still lighting the foreground, you can always angle it away or half-cover it with your hand. If you want foreground lighting too, then turn up the power of your on-camera strobes. The choice is up to your artistic instincts!
Off-camera lighting is more of a challenge than standard techniques, but this means that if we can make it work, our images will stand out from the crowd.
As is often the case, when we first experiment with a technique we want to produce images that show off the technique, while over time we start to use the technique more subtly.
Both are good, and you can be creatively daring with either.
Use a trigger sensor attached on a cable, rather than the strobe's built-in slave sensor. Effective remote strobe images invariably have the source of light hidden from view, and only a trigger with a short length of cable (0.5m) makes this possible.
Shots look most dramatic when there is no sign of foreground light, so have the on-camera strobe on low power and the off-camera high.
Backlighting is effective on subjects that are fibrous, hairy or translucent, such as soft corals, crinoids or seafans. The technique can transform the ordinary into an extraordinary image.
The key is to make certain that the strobe is entirely hidden behind the subject, and often this means looking for a subject on top of an outcrop, so the strobe can be hidden below.
Inside wrecks or caverns, dive with a buddy team. Ask one to be the model and the other to carry the strobe and aim it at the camera, with the aiming light turned on.
Now position the model in the middle and, once the aiming light is blocked from your view, you can shoot. The model will now jump out from the dark background with rim backlighting.