JOHN BOYLE has been producing underwater documentary films for almost 20 years, selling to TV channels worldwide including National Geographic, Discovery and Sky, and winning more than 60 awards. Currently completing a Solomon Islands-based film, 2009 will see him working with anacondas and humpback whales, filming British sharks, on an expedition to Newfoundland, and continuing a pet project about the seas around his Cornish home. His book A Step By Step Guide To Underwater Video remains the classic on the subject,

SIMPLE FACT - UNDERWATER VIDEO IS EASY. Its also incredibly satisfying, as more and more people are realising. Experimenting with the video capability of their digital stills cameras, they find they are getting great sequences, and recording behaviour and movement in a way in which still images that freeze a split second
in time never can.
You can record what you see under water, and enjoy editing the best of the footage, and sharing it with your friends. You can actually make underwater movies complete with music, narration and effects - watch out, Cousteau, theres a new kid on the block now!
Filming under water also adds a dimension to your diving. Once you start carrying a camera, its hard to get into the water without one!
Whereas previously you may have spotted a creature, noted it and moved on, now you can spend ages studying its behaviour as you try to shoot the best images and sequences.
You find yourself lying on a muddy sea floor, waiting for a tiny creature to emerge once again from its hole so that you can capture a special moment. OK, perhaps Im not making it sound too attractive, but wait till its you lying there,
and then remember my words!

Where do you start shopping - with the camera or the housing With the housing, in my view. Across the price spectrum, manufacturers will tell you that video cameras vary widely in what they can achieve. However, relatively few built-in functions will have any relevance when filming under water.
And if youre like me, you will be looking to adjust even fewer of these on a dive. With the odd important exception, I believe that the automatic functions on the camera are more accurate and smarter than I am!
So have a look at which housings are available on the market - there are a surprising number of variations, and its important to select one with which
you are totally comfortable - and then select whichever camera will go with it.

There arent that many housing manufacturers out there. The main ones are Canadian Amphibico, US companies Gates and Ikelite, and UK manufacturer Greenaway Marine, which produces Seapro Housings. All are available in
the UK, so researching models and prices and making comparisons is easy.
And there are three principal decisions you will need to make: electronic or manual
controls; the quality of the image you will see; and which controls are easily accessible through the housing.
Electronic controls operate by a LANC cable connecting buttons on the housing with the camera - generally on the pistol-grip handles. Manual controls use a system of knobs and levers to press buttons physically, or move switches on the camera body.
Supporters of manual controls will tell you that they never go wrong. Supporters of electronic controls will describe the ease of use of their systems compared to having to reach all round the housing in an underwater video game of table football in order to flick switches.
There is no answer; you have to make up your own mind. I find my electronic controls simple and easy to use - except when they develop an electronic glitch, the whole housing becomes unusable, I shower curses on it and vow next time to buy manual!
Vitally important is the image you see while filming. Some housings are designed so that you view the open LCD screen at the side, some at the top.
With others you actually look through the cameras viewfinder at the rear. If this is the layout, check that the magnification is good for you, and that the viewfinder shows a colour image. Some show only black and white, which makes colour-balancing extremely difficult!
With at least one housing on the market, the image you see is a reflected image of the LCD screen, so everything you see is a mirror image,
a reversal of what you are filming. This is not the easiest layout with which to work.
Another housing I have reviewed had built into the rear an excellent colour monitor. It gave great images, but it ran from a separate battery source to the camera. Those batteries needed replacing after every dive, and if they ran out during a dive there was no way of seeing what you were filming. Not the best thought-out design!
The third consideration concerns the camera functions that can be accessed through the housing. In addition to the obvious on/off/record, zoom, and manual/auto focus, it is essential that you can control white balance.
The theory of white balancing is simple - show your camera something white, and it will balance all other colours to provide natural colour.
The deeper you dive, the more the colours of the spectrum are absorbed by the water column - reds are the first to disappear. As long as your camera is told what white looks like at any depth, it will compensate for colour absorption and restore natural colour.
So it is essential that you are able to control camera white balance through your housing. If you cant, dont buy the housing. Your results will be permanently disappointing.
Make sure that not only can you access all these camera functions, but that you can do so easily. If, for example, changing the white balance is a multi-stage process, delving into the camera menu by flicking the touch screen with
a manual lever, by the time you get there your subject will probably be long gone!

Lights: do you need them The answer is yes, sooner or later you will, but when starting out, ask yourself whether you will be filming at night, and whether you will be filming inside wrecks or caves. If the answers to both are no, you will be fine initially without lights, provided you can conveniently and simply control white balance.
Once you have done your research, try to get to a dive show, where you will usually be able to get your hands on the housings and talk to the sales people about them.
The wide price range can complicate the decision. Cheap is tempting, but you could soon find that youre demanding more from your rig than it can offer. So dont be afraid to seek advice from someone who is already filming under water - we all had to start some time.

Decision made, and youre in the water. Here are a few tips that will make your footage enjoyable for you and your audience to watch.
Taking steady shots is the key. Many peoples initial footage is so shaky that when watched on a TV screen it makes you seasick!
Rather than jerking around, trying to snatch lots of bits of everything, concentrate on taking long, smooth, flowing shots. Whenever possible, use the sea floor or a rock as an impromptu tripod to hold your camera steady.
Avoid using zoom. The closer you get to your subject, the sharper the shot will be. The more the water is between you and your target, the poorer the quality, and any movements of the camera will be magnified the greater the zoom.
Start using your eyes and seeing what the camera is seeing, and use natural light to your advantage. If the sun is behind you, it will improve the lighting - if its ahead of you, much of what you film will be shadowy silhouettes.
Think about the composition of your shots. Here there is a lot to be learned from still photography, as the same rules apply.
A simple shot can become an interesting and stylish one if the subject is well-positioned in the frame. For example, if you are taking a wide-angle shot of a school of fish or a wreck, something in the foreground like a clump of weed or coral can add a new dimension to the image.
When filming a subject, actually work on that subject - dont just grab a shot and move on. Think about what you are filming, and try to capture it from several different angles.
Also, try to obtain a mixture of wide-angle and close-up sequences. Imagine, for example, showing someone your edit of a wreck dive.
If its all wide-angle shots, it will quickly become boring, but a sequence that starts with a couple of wide-angle shots, then moves to some mid-range shots and then on to some close-ups of details on the wreck, and finishes with a parting wide angle, will be far more interesting for the viewer.
You will have taken them for a tour of the wreck and told its story in much the same way as you would dive it yourself - getting a general introduction, poking around looking at closer details, and then enjoying that final parting glance.
This wreck example applies to all subjects - think while you are filming of the shots you will need later when editing. For example, if filming sharks, it is tempting just to keep the camera on wide angle; but if you also get some close-up details of teeth, eyes and fins, you will be able to tell a far more interesting story.
Shots taken looking down on fish from above rarely work well - you generally need to be on the same level, or slightly lower.
Shake off the stills photographer mindset of just collecting lots of portraits of things. The video camera is the best story-telling tool invented, and you should use this facility to its ultimate potential.
Observe creatures and film their movement and their behaviour - a film that is nothing more than a slide show will interest no-one.
Learn to stalk creatures. Rush up to them in a whirlwind of fins and bubbles and they will disappear fast. Approach gently, inch forward, and you will have far more chance of capturing your shot.
Good buoyancy control is essential in order to take steady shots, but here is a tip that goes against all the rules of good diving that you have learned - be a bit heavy; carry an extra pound or two more than you would usually.
This way, when you settle to take a shot you will be totally steady on the bottom, not starting to float up every time you take a breath.
Most of all, enjoy your filming and this will show through in your results. And remember, tape is cheap, so dont be scared to use it!

Im typing this on my laptop on a liveaboard in the Solomon Islands. I have had to escape to my cabin to get away from a classic example of bad editing.
A fellow-passenger brought with him a DVD containing his best footage from the past couple of years. Its been rolling for 50 minutes, with no sign of ending.
Sure, there are some good shots in there, but a whole bunch of rubbish too - and he knows it, because he kept apologising for the shots. So why show them to us
The first editing tip, then: if you want people to enjoy your footage, keep it short, and show only your strongest material.
No matter how fanatical the divers, they are unlikely to be kept awake by out-of-focus, wobbly, poorly coloured shots of distant and unrecognisable fish.
I escaped from the film show at the point at which the next section was introduced with the terrifying words: Next are some shots of the people who were on our last liveaboard.
Do I care Do I really want to see Phil and Martha from Minnesota waving at the camera, eating their meals and squeezing into wetsuits a couple of sizes too small for them Does anyone still upstairs in the ships lounge care
So, second tip - consider who your audience will be, and edit accordingly.
When editing, imagine showing the result to a room full of critical strangers who have seen it all before. I assure you that your standard of editing will improve!
Its tempting to make plentiful use of the effects package that comes with your edit suite, but my advice is to keep effects to the minimum, using them only when to do so actually enhances and improves the shots. Over-use of effects can be distracting, while subtle use can give your edit a sleek, professional feel.
Music and sound will also take your edit to another level, but whether thats a higher level or a lower plane depends on your selection.
Simply laying your favourite rock ballad under the images probably wont enhance the viewing experience. Think carefully about your choice of soundtrack and pick something appropriate and that works with the feel you are trying to create.
I often record local ethnic music when visiting villages on trips - its amazing how often that seems to suit the mood of my piece.
The secret to good editing is simple - try to tell a story. Be brutal and cut out all but your best shots, anything you dont need to tell that story. Never forget that you are not simply giving a slide show of unconnected images.
And learn by watching analytically other peoples films. You will soon start picking up tips on what to do and what not to do in your edits.
Have fun - youre starting out on the road to an amazingly satisfying pastime that may just become something more.
When I got my first underwater housing 20 years ago, all I planned to do was make a short video to show my son and his mates...