Monthly Archives: January 2016

  • Technological Advances in Underwater Lighting

    If you are diving inside an unlit wreck or at night, it’s pretty obvious you’re going to need some form of light and there’s a plethora to choose from. What may not be so obvious is that if you are diving in water under bright tropical sunshine, everything will look monochromatic thanks to the fact that water selectively filters the light so that more than a few metres away from the surface, everything looks blue. Not only that, but try looking under ledges for any animal that might be lurking there (and that’s where a lot of animals lurk during the brightest part of the day) and everything gets lost in deep shadow.

    A light will illuminate the corals in their true vibrant colours A light will illuminate the corals in their true vibrant colours

    So in actual fact a powerful diver’s light is just as useful during daylight hours as it is when there is no natural light by which to see your way. The difference between having a weak light and no light at all is clearly obvious too at night, but during the day you’ll need a light that can compete with the daylight, filtered as it is by the water. That’s why you’ll see successful underwater photographers using powerful underwater strobes to light up their subjects and videographers often using powerful video lights.

    Years ago, underwater lighting was limited by the size of the battery that could fire up a conventional halogen lamp. Powerful lights tended to be both huge and heavy. More recently, lithium-ion battery technology combined with modern LED bulbs can give us a powerfully bright light with a useful burn-time combined in a compact package.

    A lamp will light the way wherever there's no natural light. A lamp will light the way wherever there's no natural light.

    A good example of that is the Nanight Sport dive torch. This Swedish torch uses a cluster of three Cree XM-L2 U2 LEDs in a single module to push out up to a massive 3000 lumens fired up by its lithium-ion battery pack and the beam so produced can either be a narrow 12° suitable for those diving in low visibility conditions and who want a tight penetrative beam, a 35° beam that is generally very useful, or a wider 55° beam for those diving at night who may be a little nervous about what might be close by but not immediately lit up. It’s important to choose the appropriate one for your needs.

    Kansho4619 Inside the engine room of a wreck.

    For example, I took a torch limited to a narrow beam on a trip to dive the wrecks of Truk Lagoon. It was a mistake. Swimming about inside the engine rooms and holds of these 1944 relics from the Pacific War, I missed a lot of details because the beam was too selective. The next time I went I made sure to use a torch with a wide beam and missed nothing.

    The burn-time at a full 3000 lumens is a little under one-and-a-half hours, which is more than enough for any daylight dive when you might need the maximum intensity, but you can progressively dim it in four stages and the burn-time increases pro rata. This is effected by a magnetic switch that functions sequentially and a micro processor controls the light intensity. If you are worried that the light might overheat, the LEDS are temperature monitored.

    You might find that 750 lumens is quite enough once your eyes have adjusted to the darkness and should you be doing a series of leisure dives on wrecks, there will be more than enough power in the battery for a full day’s diving, with some to spare. You’ll only need to recharge the torch once each day.There is a battery charging indicator that turns from red to green as it is charged. Recharging from flat takes a few hours and before the light extinguishes due to low battery power it continues with progressively lower light output. That equates to something of a get-you-home mode.

    Nanight Sport Nanight Sport

    All this technology is contained within a tube that is around 15cm long and 5cm in diameter. It weighs a mere 500g and is depth-rated to 100m, which is enough for most people! When you first switch it on, it flashes up to four times to indicate the state of battery charge.

    If you want an even longer burn-time, the Nanight Tech dive torch uses a similar head that is powered via an umbilical by a larger 20cm long battery pack and weighs around a kilogram. It will run for two-and-a-half hours at full output with an extra hour with gradually reducing light output. The battery canister attaches to your tank, backplate or other convenient place and the head, only 8cm long, is supplied with a Goodman handle that allows hands-free use. It comes with the two reflectors for the narrower beams.

    Nanight Tech Light Nanight Tech Light

    One last point: When using extremely bright lights like these, avoid shining them towards the eyes of other divers. If you wish to signal, point the light at your signalling hand.

  • The Philippines

    Did you know that the Philippines have more miles of coastline than almost any other nation? That's because they are a multitude of islands and the diving is diverse as the people that live on these islands. The Philippines have only recently become popular with divers. We don’t know why, but often when customers at Ocean Leisure are buying lots of stuff for a trip, we ask them where they are off to and more often than not they are set for a trip to the Philippines.

    A typical bangka boat. The design draws little water so the vessel can be driven right up onto the white sand beaches. A typical bangka boat. The design draws little water so the vessel can be driven right up onto the white sand beaches.

    Whether you are planning to cruise around the Camotes Sea in a bangka boat (visiting Malapascua in the north or the jetties of South Leyte or Bohol in the south), diving the World War II wrecks of Coron Bay, enjoying the varied diving out of Puerta Galera with nearby Verde Island, visiting the green turtles at Apo Island and marvelling at the the macro life, muck diving at Dumaguete, or setting off from Puerto Princessa aboard a liveaboard dive boat to visit the remote reefs of Tubbataha, the diving will never cease to amaze you and make you wonder why you left it so long.

    Typical Jeepnee with plenty of chrome. A Jeepney with plenty of chrome apparent.

    You can get to Manila via HongKong or Singapore, for example and whether you make landfall in the city of Cebu or the capital Manila, more often than not you will need to connect via a local airline to get to where you intend going. The Filipino people are extremely welcoming and well travelled. The greatest export from the country is its people and everyone you meet is either back from Europe or North America, is about to head off there, or at least knows some members of their family who are doing so.

    Filipino people offer an extremely warm welcome. The Filipino people offer an extremely warm welcome.

    Nearly everyone speaks good English so nothing is difficult for the Brit abroad in the Philippines. A popular vehicle is the Jeepny, originally developed by converting WW2 Willys Jeeps but now manufactured locally in the same style but enlarged.

    During my career, I regularly travelled via Manila to other destinations in the middle of the Pacific but it was only towards the end of my career that I decided to stop off and dive in that country.

    I was knocked out by the quality and the variety of the diving. If you are an underwater photographer  you'll need to take both macro and wide-angle set-ups. One dive you'll be photographing pigmy seahorses or elusive mandarin fish and the next it will be whalesharks in front of your camera!

    Tiny mandarin fish only conduct their courtship rituals in open water during the first moments of nightfall. Tiny mandarin fish only conduct their courtship rituals in open water during the first moments of nightfall.

    One moment you're looking at a seahorse and the next it's a whaleshark! The author at work. One moment you're looking at a macro subject and the next it's a whaleshark!

    Whether you shoot with a sophisticated DSLR, a micro four-thirds camera or a compact, we can supply you with any accessory lens set-ups that you might need to make the most of your trip. All we ask is that you don't leave until the last minute and call into the Ocean Leisure store on you way to the airport! (you'd be amazed at how many people do that!)

    Some of the places you might stay in the Philippines will be decidedly 'developing country' style while others will compete with the most sophisticated resorts in the world. It's all about budget and you can get by in the Philippines on a very small one. What about the weather? Well, nearly every autumn the Philippines get into the news when the islands are inevitably hit be a typhoon. However, they are quick to rebuild and by the time you go in the Spring, everything will be back to normal.

    Instead of passing through Manila or Cebu on your way to some Pacific destination, why not stop off and savour what the locale has to offer? The Philippine offer some of the best tropical diving in the world. We know it well. Next time you pass by the Ocean Leisure store, stop by for a chat and we'll try to advise you of the differences between the different locations  within this tropical archipelago. Enjoy!

    Turtles and jacks. It's busy underwater at Tubbataha! Turtles and jacks. It's busy underwater at Tubbataha!
  • The Magic of RAW Files

    You might have heard RAW files being mentioned when you were sold your camera. You probably shoot jpegs. However, many cameras today can shoot RAW files, even some of the most basic compact cameras. Most serious underwater photographers shoot RAW files rather than jpegs, or they shoot both concurrently. So what's it all about?

    When you shoot a jpeg, the in-camera processor uses an algorithm to save the picture in a file form that is compressed and doesn't take up much space on the memory card. If you can set your camera to record RAW files, the memory card records everything that is picked up by the camera's sensor. It means that instead of relying on an algorithm written in some far off part of the world, you can manually translate your picture using your home computer later.

    Capture1On the left is a picture that equates to what would have been recorded as a jpeg at the time. It's not very good, is it? The photographer had his camera set incorrectly and would have had to have adjusted his camera in a suitable way to get a properly exposed shot.

    The contrast is too high, the highlights have burnt out and the subject is disappearing into the background.

    If you look to the right of the picture you will see Capture2some controls. This is the original RAW file displayed on the screen of a home computer (PC or Mac) using a proprietary RAW converter program. The controls on the right have sliders that can be adjusted for colour and hue, exposure, contrast, highlight detail, shadow detail, whites and blacks, clarity, vibrance and saturation.

    Now given time and a co-operative subject, the photographer may have been able to adjust his camera and flashgun to get a similarly acceptable jpeg but this is done at home long after the dive is over and without the time constraints caused by being underwater. Here's a close-up view of those controls:

    The RAW file is left unaltered and can be safely stored for future use and maybe an alternative interpretation. In the meantime this version is saved as a jpeg.

    Now you may prefer the instant gratification of getting it right in camera but what if the subject is not co-operative. What if it's a moment in time that you have just managed to grab. Maybe it's an image of a fast-moving shark that happened to come close to your camera for a moment.

    You won't have a second chance. You may still have your camera set for the previous picture you took. You just press the button and hope for the best.

    If you have shot a RAW file you will have the option to decide on all the camera settings, save for focus, long after the event.

    Not only that, but there are layers and layers of controls, some of which are quite advanced, but there is nothing difficult about using them. You just move the sliders about until the result looks satisfactory to you on your computer screen. A histogram helps make sure you don't overdo it. You cannot damage the original RAW file. You have that safely stored.Capture4

    A good friend of mine shot a picture of two dolphin. He was over-the-moon with the result and sent it to me. I thought it was so blue it was monochromatic but he was happy because it reminded him of the moment. He still remembered the colours and they were still apparent to him. They were not to me.

    Capture3I asked him if by chance he had also shot a RAW file. Luckily he had although at that time he didn't know what to do with it. He now knows! Once he saw the difference and once it was explained to him how easy it was to convert the RAW file in an adjusted way, provided he had the right software and plug-in to suit his camera file, he too was converted!

    As iconic underwater photographer once said, if you are not shooting RAW files you are missing the point of digital photography.

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