Page 102 - AlertDiver_Winter2013

100 | WINTER 2013
I ’ve long been a fan of slow shutter speeds in
underwater photography, probably since my earliest
experiments with wide angle. I remember having to
illustrate the 25th anniversary of John Pennekamp
Coral Reef State Park in 1985. The Christ of the Abyss
statue is the iconic symbol of the park, and my thought
was to combine it with some kind of pyrotechnic to
be celebratory. I found some flares that would burn
underwater, and my model held them behind the statue.
Here’s how slow shutter speed came into play: At midday
in the shallow water at the top of the statue (about 15 feet
deep), the bright ambient light from the sun would have
overpowered the flares. So I planned the shoot for very late
in the afternoon. This meant more of the sun’s light would
bounce off the water’s surface than would penetrate it —
due to the oblique angle of the setting sun. My light-meter
reading would be several stops darker at that time of day. I
used a strobe to front-light the statue and my model, but the
low ambient light allowed me to set my shutter to 1/30 of a
second (the slowest shutter speed on my Nikonos camera),
and that gave the light from the flares more time to register
on film, making them appear brighter.
I have used this technique more recently when shooting
product illustrations for dive lights. There is a huge
difference in how bright a dive light will appear when
the camera shutter is open for 1/250 (the fastest strobe-
synchronization speed) compared to 1/15, for example.
If we accept that the exposure from the strobe light is
essentially a function of strobe power, strobe-to-subject
distance and subject reflectance, it wouldn’t really matter
Celebrating Slow
Using slow shutter speeds for creative effects
T e x t a n d P h o t o s b y S t e p h e n F r i n k
IMAGING // P H O T O T E C H N I Q U E S