His first renderings were home-made, using plumbing fittings and old Biro bodies held together with gaffer tape. The results were images that displayed his subjects beautifully isolated in spots of light against black backgrounds.
Keri’s images took the underwater photography world by storm, and the good old snoot became fashionable all over again.
Modern snoots have become very hi-tec, none more so than the latest light-shaping device from Slovenia-based Retra Underwater Technology. Photo guru Alex Mustard generously lent me his to try out.

Why Use Snoots?
The main reason for using a snoot is to isolate the subject, putting it in a spotlighted pool of light as if it was on a stage. Snooting allows the strobe light to be projected directly where you want it, which also helps to eliminate distracting negative space. By using fast shutter speeds and small lens apertures, you can render this background black, even in bright daylight.
Another advantage of using snoots is that they decrease the beam angle, making it easier to control stray light and minimise backscatter.
Also, the light can be directed onto the subject in such a way as to dramatically emphasise textures, giving a creative feel to the final image, and they can be used behind the subject for backlighting.

The Early Days
When Keri built his first snoots they were simply tapered tubes that funnelled light by blocking it from the strobe until a small illuminated point remained. The strobe had to be positioned with the tip of the snoot very close to the subject, so the point of light was kept to the desired size, and also remained bright.
The big drawback with using these tube-type snoots was that they restricted the light and wasted most of the strobe’s output.
Indeed, Keri had to shoot at night to reduce the chance of bright ambient light overcoming the snooted strobe light.
The close proximity of the snoot tip also meant that subjects were limited to those that didn’t spook easily, or were very slow-moving. What was needed was a device that didn’t do this but would instead focus the light-beam into an even column, thereby increasing the output and working distance. Enter Retra’s LSD.

The Design
Retra’s light-shaping device consists of three components. The first is a light-collector, which gathers the light from the strobe with minimum loss using polished reflective surfaces.
The second component is a tubular housing fitted with internal lenses to project the light in a column onto the subject.
Lastly, there are the light aperture masks, which slot behind the lens barrel and determine the size and profile of the light beam.
The LSD fixes to the strobe face with a clamp, which is part of the light-collector and is “strobe-model specific”. Retra has various options to cover the most popular makes and models of flashgun.
The light-collector is made of polycarbonate and comes in two models, clear or black, the latter being the version used on test.
The lens housing is made from anodised aluminium with O-ring-sealed polycarbonate lenses. The complete LSD has a body length of 215mm, weighs in at 700g and is depth-tested to 6 bar.
Each mask card has different-sized apertures of the same shape. Four cards are supplied with differently shaped apertures, from squares to diamonds and circles to twin pin-pricks, for possibly illuminating just a pair of eyes.

In Use
I took the LSD Prime on a trip to the Maldives, knowing I would find plenty of suitable subjects. It seemed an ideal opportunity to have a go at producing the kind of images with which Keri had wowed the world.
I set my camera up with a 105mm macro lens and clamped the LSD to an Inon Z240 strobe. Finding a small blenny in a hole in the coral, I set the strobe distance and direction using a tiny stone about the same size as the fish and, once the camera was focused on this point, set it to manual focus.
To shoot the blenny, all I had to do was rock the camera gently backwards or forwards until the little fish was sharp in my viewfinder and pull the trigger, in the knowledge that the snoot was aimed to illuminate it perfectly.
Well, that’s the theory. In reality it took the best part of 20 minutes to get the snoot aimed in combination with the right focal distance. The reason for this was that I couldn’t see the aiming light from the strobe on the stone, because the bright ambient light from the sun overcame it.
When I had eventually achieved the setting-up process I accidentally nudged the strobe arm as I was getting into position in front of the blenny. Doh! I’d have to start all over again.
It took a whole dive to get a couple of out-of-focus, poorly lit shots. I tried again on other dives but got increasingly frustrated by my shortcomings. The snoot was proving difficult for me to use.
The answer was to dive a little later in the day, making it easier to see the aiming light. In darker conditions it worked like a dream, and I was able to get some useable images of a sexy anemone shrimp highlighted in a small pool of light.
Back home in my studio, I set the snoot-and-strobe combination up to shoot a small toy to demonstrate its capabilities for this test, and found it a doddle to use.
Targeting the strobe by hand while actually in front of the subject was by far the easiest method, but only because I could clearly define the aiming light through the camera’s viewfinder.
Keri used to mount his snooted strobes on a gorilla-pod rather than the camera, meaning that once set he could move about with his camera to get the best angle of view. I didn’t try this, but it makes perfect sense.

Although I made a hash of the tests, it was apparent that all I needed was a little more practice, a lot more patience and a better understanding of the technique required to get the most from this simple if (for me) frustrating bit of kit.
The Retra Prime LSD is a well thought-out and beautifully crafted photographic accessory. In the right hands I know that it’s capable of delivering the goods – the studio session proved that to me.
I’m also acutely aware that I should get one to add to my own photographic arsenal, and spend time perfecting the skill needed to get the most from it. The results from those who have mastered this genre of underwater photography have been astounding, and I don’t want to be left in the dark ages.

PRICE 343 euros, spare mask set (four pieces) 29 euros, advanced mask set (10 pieces) 99 euros
STROBE COMPATIBILITY Ikelite, Inon, Sea & Sea, Seacam, Subtronic
CONTACT www.retra-uwt.com
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