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X-Ray Mag #62 - Sep 2014
X-Ray Mag #62 - Sep 2014
X-Ray Mag #62 - Sep 2014
X-Ray Mag #62 - Sep 2014
X-Ray Mag #62 - Sep 2014
X-Ray Mag #62 - Sep 2014
X-Ray Mag #62 - Sep 2014
X-Ray Mag #62 - Sep 2014
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Apnea Pix

Taking pictures while freediving can be a real physical challenge, but in some cases, it may be the only option to get the subject in front of your lens.
Apnea Pix
Published in X-Ray Issue: 62 - Sep 2014
Authored by: Kurt Amsler | Photography: Kurt Amsler | Translation: Peter Symes
Download pdf ► Apnea Pix
Freediving in order to take underwater photographs is not the norm, but there are many freedivers who do just that—for example, the freediving icon Fred Buyle.
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It is also a good technique to use for practical reasons; Without noisy bubbles, it becomes possible to get closer to shy creatures. But the main advantage is that it’s easier to keep up with fast moving animals, such as marine mammals and sharks, when you do not have to propel bulky scuba apparatus through the water, too.

The kit
Compared to the scuba laden shooter, the freediving photographer tends to swim further and faster, so camera rig and equipment need to be optimised for these circumstances. The choice of diving equipment is also important, which will be discussed in further detail below.

The goal is to keep the camera as hydrodynamic and compact as possible. While artificial light is needed, only one flash unit should be mounted. A double-flash configuration would produce substantial drag and appear too large to an animal, scaring it off. In general, the classic apnea subjects—such as whales, dolphins, sharks, manta rays and other pelagic marine animals—live in the surface layers of the sea where ambient light is sufficient.

But even without a flash, the housing should have as little resistance as possible. Big dome ports, from 18cm of diameter and up, produce significant drag, so if you plan to pursue freediving photography more actively, you should consider getting a smaller dome. However, there are a few points to be observed.

The smaller the diameter of the dome port, the less depth of field we get for a given aperture. This is related to the imaginary image the dome as a spherical lens projects in front of it. Using a 22cm dome, you may still achieve a full depth of field with an aperture of f:2.8, whereas with a 18cm, you will lose about a third of that. To compensate, the aperture needs to be stepped down to 5.8 or 8 in order to achieve a complete depth of field. For even smaller ports, the effect is even greater.

Back in the film (or analog) era, using ASA/ISO 100 using apertures from 2.8 to 4.5 were the order of the day, which is why the super dome ports were required to achieve full depth of field. Today, with modern cameras, where 400 to 600 ASA / ISO can be used without loss of quality, such large apertures are no longer relevant. Even under the most difficult lighting situations, it is rarely necessary to open up the aperture further than 5.6.

Exposure
When working with flash, everything is the same as before, and classic flash techniques come into play, depending on whether wide-angle, standard focal length or a macro lens is used. The flash takes priority and is controlled by the aperture after which the capture of ambient light from the background is dictated by the shutter speed.

When working only with natural light, these rules no longer apply. Where a flash is not used to freeze the motion of fast moving animals, one depends on shutter speed. This must always be set faster than the relative movement between the subject and photographer, which of course depends on the situation. For example, when you approach a floating sperm whale, the shutter speed must be at least 1/350 seconds to ensure no motion blur occurs.

Ensuring correct exposure is then controlled via the aperture setting. In daylight photography, the camera can be used in automatic mode. With the camera set on “Shutter Priority”, we do not have to care about anything, even if the lighting conditions vary. Only in situations where there is strong sunlight coming in from the side, or in front of the camera, which should be avoided anyway, the +/- exposure correction can be set at approximately 2/3 stop of overexposure.

It is, of course, also possible to use the camera in “manual” mode and use the built in light meter as a guide, but I generally recommend using an automatic mode in order to save time. Once again it should be emphasized that shutter speed takes priority, and aperture and exposure is less important.

Should the aperture, in the case of too little ambient light, start to go below a value of 8 or 5.6, increase the ISO value rather than reducing the shutter speed!

Getting the shot
The difference between shooting while freediving and shooting while scuba diving is that the photographer usually has virtually no time to get the subject in front of the lens, let alone to mess about with camera settings. In other words, all important settings must be made prior to the dive. Already at the surface, the photographer can see the subject, assess the situation and decide from which side it is best approached, and then adjust the camera settings accordingly.

A proven trick when capturing marine mammals, sharks and schools of fish is to preset the focus, so that the autofocus will not go hunting among several moving subjects. For example, while holding your legs out straight, focus your camera on the tip of your fins. Then flip the AF / M switch from Aufofocus to Manual focus, which will then leave the focus setting where it is.

Since we usually work with the aforementioned subjects with super-wide angle or even fisheye lenses anyway, a f: 8 aperture will produce a depth of field from about 80cm to almost infinity. To benefit from this old trick, the underwater housing must, of course, have such an AF/M switch.

When working with natural light, the subject should appear fully lit, which means that you should approach the subject with the sun at your back. With the sun coming in from the side or even from the front, the subject tends to appear too dark against the background and the water can appear cloudy and dull, too. Exceptions are, of course, deliberate creative choices or backlit scenes.

Diving technique
It is not just the camera gear that needs to be streamlined, so does the dive equipment. Consequently, freedivers equip themselves accordingly—with tightfitting, smooth suits, long fins, masks with small volumes and short simple snorkels.

Breathing technique, pressure equalization methods, etc, remain the same for the most part, but may be adjusted according to the shooting situation. It is, for example, impossible to calmly prepare for a dive while swimming alongside a whale shark.

It is important, whether diving with or without a camera, to get the weighting correct so positive bouyancy will be set in at around six meters of depth.

Equally important is to not exceed dive times beyond training levels and to be mindful of safety. It is only too easy to become fascinated with a particular subject in the viewfinder and ignore or suppress the respiratory stimulus and hunger for air for too long, increasing the risk of hypoxia or shallow water blackout just below the surface.

To this effect, multiple U.S. champion, Terry Mass, developed the freediving lifejacket. The “FRV” (Freediver Recovery Vest) is equipped with a timer and depth gauge, which can be individually programmed to suit personal needs. The vest is automatically activated depending on the programming, or by hand.

The FRV consists of two bladders, which fit very snugly, and a small neck part, which houses the electronics. It does not prevent any freedom of movement and has little water resistance. The volume of the bladder is 16 liters and is equipped with two 38-gram CO2 cartridges, which will provide sufficient lift from depths of up to 45 meters.

Color correction filter
I also recommend bringing the so-called “Magic Filter”, which, at depths from about six meters to about 15 meters, depending on water clarity and sunlight, will restore a large part of the colors that are otherwise lost by absorption.

The principle is based on the conversion of color temperature and color balance. This unique invention takes advantage of the technology that comes with modern digital cameras and is primarily designed for wide angle and fisheye lenses. For shooting against the surface and at depths less than six meters, it is not well suited as the ambient light will appear lacking magenta.

Using Magic Filters where no artificial light may be used is a no-brainer, but for greater depths and sunless days, it is best to do without it. The filter only works optimally in bright sunlight and clear water. And the colors are the most beautiful when the subject is fully illuminated.

There are Magic Filters for the most popular and super-wide fisheye lenses. Recently, they have also been produced for compact cameras. For more information about sizes and compatibility, please visit www.magic-filters.com. ■

For more information about Kurt Amsler and his underwater photography courses, please visit his website at:
Photosub.com

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Apnea Pix
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