While there are quite a few tips and tricks I can suggest, these are the six „cardinal” rules that I think every underwater photographer should know. Even though there are nine tips in all, these six are undoubtedly the most important.

Tip 1. Spend, Spend, Spend. This is one of those pearls of wisdom that is easily dispensed but hard to follow. If you are in the market for an underwater camera system, and have a serious interest in photography, max out your credit card. The old joke about „always live within your means, even if you have to borrow to do so” applies to underwater photography. Here’s why: Decent point-and-shoot cameras are becoming increasingly expensive, starting at around $300 to $400.

If you are interested in more than merely snapshots of your dive vacation, you will soon discover the limitations of these simple cameras. Typically, point-and-shoots have a weak built-in flash. When the resulting photos are underexposed, you’ll soon understand the need to buy a stronger strobe for those wide-angle shots. There’s your first additional fee. But to get those wide-angle shots, you need a wide-angle lens.

Normally, point-and-shoot cameras don’t have interchangeable lenses so you’ll have to buy a supplementary lens that slips over the primary. There’s your second additional fee. Now throw in some accessories like an adjustable arm for the strobe, an optical viewer that lets you frame the wide-angle lens properly, and now your „beginner” camera system cost you close to $1000.

But at $1000 you don’t have a great underwater camera system, you have an adequate one. You still have an extremely limited choice of strobes and lenses that you can use, and none of the advantages of „professional-quality” equipment (see Equipment Guide section) Spend the big bucks and get a system that will grow with you. Which segues nicely into…

Tip 2. The Nikonos
For underwater photography my wife and I both use a Nikonos V. It’s one of those products that keeps getting better with each new release. If you already have an extensive collection of camera bodies and lenses, it might be a better investment to get a housing for your system. But if you have no compelling reason to purchase a housing, buy a Nikonos.

Even though I prefer a housed camera for some uses, I will always rely on a Nikonos as well. While I like to trade off between a housing and the Nikonos, my wife uses a Nikonos exclusively. It’s lightweight, compact, rugged, and most important, completely expandable in terms of lenses and strobes. In its latest incarnation –the Nikonos V– the camera even features TTL metering. For dependability and ease of use, the Nikonos is still the best underwater camera made.

Note: The Nikonos has been discontinued, unfortunately, though they are still available from some retailers and auction sites like E-bay.

Tip 3. Use a low speed film and a strobe
Both the film and strobes section covers this tip in detail, but the short explanation is this: unless you use a strobe in conjunction with a low-speed film, you’ll never be able to achieve fully-saturated vivid images.

Tip 4. Invest in a Super Wide-angle Lens and a Macro Lens
I really consider it an investment, not an expense. No other combination of lenses will give you such utility or professional results. A list of specific advantages is covered in the lens section. While I’ve used an entire range of lenses, including zooms, normal wide-angles and standard lenses, I now rely entirely on those two types of lenses. In fact, probably 95% of the pictures in the Galleries section were taken with that combination. If you are using a housing, buy a macro lens for your camera. If you are using a Nikonos, buy extension tubes or the close-up kit. One of the great advantages of macro photography is that the least expensive solution, a Nikonos with a 35mm lens and extensions tubes, is the easiest form of underwater photography to learn, allowing even a novice photographer to take consistently professional pictures.

Tip 5. Pre-focus
When I’m using a Nikonos, I generally prefer to „pre-focus” my camera at the beginning of a dive. This means that I set the distance, aperture, strobe position, and optical viewer for a preset distance. I decide, for example, that I’m going to shoot at 3 feet with my 17mm super wide. If my subject is out of range, I find it much easier to approach or back away from the subject than trying to chase it down –while simultaneously adjusting those four settings.

A lot of people ask me if I miss any shots that way. The simple answer is yes, I do. Occasionally. But not often. The alternative –and I’ve seen this often– is to constantly adjust the camera settings for every photo opportunity that arises. The problem with this approach is that just as soon as the photographer adjusts all the settings the subject often moves out of distance –and now the photographer has to reset everything again. But by the time that happens, the subject has moved again and…
If I’m doing something as critical as macro photograph with a housing (which allows the use of thru-the-lens focusing), I still prefer to pre-focus for the most part. I merely „lean” forward or backward a bit until the subject comes into focus in the viewer.

I’ve seen some wacky underwater photographers in my time. I’ve actually seen divers crash head first into a reef, so intent were they on adjusting their camera settings while chasing down their subject. I think my approach is much reasonable. At the very least, it’s certainly less embarrassing or painful. That doesn’t mean that I won’t occasionally change the settings on my camera when a subject I want won’t stay within my pre-defined range, but as a practice it’s much easier to wait for a subject to come to you than vice versa.

Tip 6. Know the Guide Number of Your Strobe
All of the pictures in the Image Galleries were shot in manual flash mode. Here’s why I brought up the subject, since it reinforces the importance of guide numbers. I believe in trying to keep diving and underwater photography as simple as possible. Too often I’ve witnessed sophisticated and expensive electronic equipment failing over something as frustratingly stupid as a 50-cent component that goes bad, or a $5 battery that can only be purchased from the manufacturer. When sophisticated technology fails, it’s nice to have a simple backup that won’t fail you, one that doesn’t rely on technology at all. Here’s a case in point…

Just prior to my departure on a dive vacation to Roatan, I finally took the plunge and bought myself that painfully-expensive integrated housing/camera/strobe system that I had been dreaming about from the moment I read about it. Regrettably, I didn’t have time to test the system before I left. Predictably, since this was the only time in my life that I failed to test new equipment, the outcome was inevitable. Though I had always used guide numbers in the past to determine exposure, I decided to shoot in TTL mode (automatic flash metering). Why? Because I stupidly reasoned that a brand new $900 strobe would work on its first time out, and I might as well take advantage of its „advanced” features.

I spent the next two days of an expensive dive vacation blissfully shooting away. It wasn’t until my first night dive there that I realized the power output was wrong. In bright daylight it’s often difficult to gauge strobe output, but at night it’s relatively easy since there is no overpowering sunlight to mask the output. Since I was doing macro photography, I knew that at such close distances the strobe should have been outputting a fraction of full power. Instead I was being blinded: the strobe was firing at full power. Constantly. Once I understood the problem, it was easy enough to switch to the manual guide number method of determining exposure. It was just as easy to realize that all the film I shot previously would be overexposed and useless. („Hey, George, are you ever going to explain guide numbers?” –OK, I’m getting there. Here is comes).

At first, the concept of guide numbers seems antiquated, even difficult to some („You have to do math in your head? –while underwater?!”) But after you’ve practiced with it a bit, guide numbers are really easy. And since it’s only one number that you have to remember for each film/strobe combination, you avoid Murphy’s Law with respect to sophisticated technology

Guide numbers are a way of rating the strength of a strobe’s output. Essentially it is a ratio between aperture and subject distance, using film speed as a reference point. If this seems incomprehensible, let me give you an example. Suppose your strobe has a guide number of 32 with a film rated at 50 ISO. That’s the important part: Guide number 32 with 50 film. If you want to illuminate a subject 4 feet away, set the aperture on your lens to 8. Why? Because 32 divided by 4 = 8. If the division doesn’t work out neatly, use the closest aperture that fits. For example, set the aperture to f11 if the subject is 3 feet away (32 divided by 3 is 10.6) Since there’s no aperture f10.6, pick the closest one (f11).

I’m not suggesting anything as difficult as mentally calculating fractional division underwater. Consider the previous example. If the subject is 3 feet away, and the strobe’s guide number is 32, you know that dividing the two will give you 10 and some fraction. Just look at your aperture ring at that point. F11 is the closest number to 10. That’s it. Strobe manufacturers often place decals or dials on the strobe that list the various correct settings.

Actually, the concept of guide numbers gets even easier with a little practice. Once you know the guide number of your strobe, there are generally only certain combinations you will ever use. For example, on my Sunpak Marine 32 these generally only settings I use:
2 feet = f16
3 feet = f11
4 feet = f8
I don’t bother memorizes other setting. If for some reason I decide I want to shoot a subject 6 feet away, I can easily determine the proper aperture setting: 32 divided by 6 = 5 and some fraction. So I set the aperture to f5.6. Again, that’s all there is to it.

To determine the proper guide number you’ll need to do a controlled test. For example, try a series of test shots in a pool. Position your subject your 3 feet away. Now take the first picture at f4, then f5.6, then f8, then f11, etc., and write them down on an underwater slate (picture 1 = f4; picture 2 = f5.6, etc.) After developing the film, look for the best exposure. Assume the correct exposure was f8. Since you were 3 feet away and the correct exposure is f8, your guide number is 24 (3 times 8). Just remember one thing about controlled settings like a pool: they are idealized. In other words nice reflective white walls. If you’re going to do this type of test, make sure you position your subject away from a reflecting wall and shoot towards open water.

Tip 7: Never Lend Out Your Photo Equipment
I know it sound heartless. It’s a hard lesson to learn but experience has taught me that nobody will care for your camera equipment like you will. It’s an expensive mistake rarely repeated. Having worked in underwater photo labs in the past, I have witnessed dozens upon dozens of flooded or dropped cameras, scratched lenses and lost cameras („Gee, I left it out on the beach and I was only going to be gone for a half an hour, whaddya mean I’m responsible?”). In most cases, they were the result of complete indifference on the part of the borrower: they didn’t pay for it, so why should they care? Furthermore, underwater cameras and strobes require a great deal of maintenance. Even if it’s your most trusted friend, generally only you will invest the time in learning how to maintain the equipment properly.

Tip 8. Test all New Equipment in a Controlled Situation First
It’s a hard lesson to learn but an easy one to remember after something has gone terribly wrong. If your equipment fails you, or worse yet floods while you are in a remote location, it’s too late to do much about it.

Test the integrity of a new housing by submerging it in a pool without the camera in place. Work all of the controls. Even in only 8 feet of water you’ll soon learn whether it’s sealing properly or not. If you’re satisfied, try the same thing with the camera inside and the strobe connected. Fire off a few shots to make sure the film is advancing and the strobe is synching properly. In the following tip I describe an incident where this simple procedure would have saved me endless frustration, time and money.

Tip 9: Learn How to Maintain Your Equipment
Underwater camera equipment requires constant maintenance. Learn how to do basic maintenance suggested by the manufacturer. Keep the o-rings clean and lightly lubricated with silicon grease. Never leave your camera in direct sunlight –at the very least it will melt the emulsion on the film. As soon as possible, rinse all the camera equipment in fresh water, preferably warm water (not hot).

Buy a protective cover for your lens. Then take it with you on the dive, and replace it before you get back into the boat. Dive boats operators will often grab a camera from a diver as he emerges from a dive and place it face down on the deck. This practice is especially dangerous for super wide-angle lenses since the front element (or dome port, if it’s a housed camera) generally protrudes beyond the rim of the lens. They are easily scratched and expensive to repair. The last piece of advise on this subject of maintenance is this: always bring a small toolkit, with spare parts, on your dive trip. A case in point…

When I was much younger, but just as foolish, I had the opportunity to dive in Moorea. For a fledgling underwater photographer from California, the prospect of warm, clear tropical waters was a dream come true. Unfortunately, no sooner had I arrived in Moorea when I began being plagued by camera housing problems.

At first, they were minor problems that could have been fixed easily with a few simple tool like a jeweler’s screwdriver, but soon graduated into the more serious problem of a loose connector wire that needed soldering. Needless to say, I couldn’t even find a small screwdriver where I was staying, let alone a soldering iron. My dream come true soon became a crushing disappointment, and I went several days without being able to take pictures.

Fortunately, I finally met a fellow diver there who had the foresight to bring a small toolkit along (and, yes, even a soldering iron) and we managed to get the system working again. Naturally, we got it working two days before I was leaving, and that incident started my hate/hate relationship with one particular manufacturer.

Make sure you have your equipment serviced by a professional outlet and according to the manufacturer’s guidelines. A Nikonos costs about $100 to service. While I think that is expensive, it cheaper than replacing a flooded camera. Also, reputable service outlets will pressure test the camera after servicing.