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an undesirable digital artifact that obscures the image; it
varies from camera to camera but increases with relative
ISO.) We have found that the sweet spot in background
exposure changes with dive site, camera angle, time of day
and depth, so remember to reference your digital camera’s
LCD screen. Evaluate the histograms and graphic display,
and adjust accordingly throughout the dive.
You’ll have no shortage of foreground subjects:
anemones, sea stars, gorgonians and the kelp itself abound,
but sometimes the visibility can be very limiting. Our
recommendation is to use the “10-percent rule” — shoot
your chosen foreground subject within 10 percent of the
total visibility. If the visibility is 20 feet, you should endeavor
to be no further than 2 feet away from your subject.
The basic principles of strobe positioning are also
important. We prefer our strobes be the same distance
from the sides of the housing as they are from the subject,
so the closer you are to your subject the closer your strobes
should be to your housing. At times, this will be very close
indeed. In extremely challenging conditions, we have even
used wide snoots to light an isolated foreground subject in
an attempt to limit backscatter. Finally, as painful as it is to
admit it, some days are better thought of as practice days
since you won’t get a single image worth keeping.
Big Critters in the Kelp: Be prepared
Since kelp forests are so nutrient-rich, they attract
schooling fish and an amazing array of large predators,
including sea lions, seals, rays, sharks and giant sea
bass. Beautiful gelatinous invertebrates such as jellyfish
and salps can also be encountered, and we have even
been fortunate enough to witness a chaotic market
squid mating ritual (the so-called “squid run”). These
opportunities cannot be planned in advance, so
photographers must be prepared to shoot, adjust and
reshoot rapidly.
When we are hoping to photograph larger, faster
animals we use “grab-shot” settings that include a shutter
speed adequate to capture fast motion (1/125 sec at
a minimum), balanced with relatively open apertures
(f/5.6 to f/8, depending upon conditions, subject size
and anticipated distance from the subject). We pull our
strobes out to the sides and behind the center line of the
housing to minimize backscatter and flare and then set
them at a quarter to half power to enable short recycling
times. Strobe positioning, strobe power and camera
settings are adjusted as needed when we encounter
creatures that don’t immediately disappear. As with most
other subjects, patience and getting as close as possible
are the keys to success.
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SUMMER 2012
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P H O T O T E C H N I Q U E S