What's the Point?
First, you need to think about what you want to use the camera for - and this in turn helps to determine your budget. If you simply want to take a few snapshots from your dive holiday & are not so interested in learning the finer points of underwater photography, then a point & shoot model, such as a Sony Cybershot or Canon Ixus should suffice.
If you are interested in learning a little about underwater photography & having a few controls at your disposal to improve your image making skills, but feel that an SLR is a step too far, then there are a few great consumer digital cameras on the market that offer full manual controls, such as the Olympus SP350 or Canon A540. These models are still relatively inexpensive, but allow you to develop your skills and adjust vital settings like shutter speed or aperture as your confidence grows.
Finally, if you really want to splash out and are interested in taking very high quality images for entry into competitions or for publication, then you need to look at Digital SLR models.
The Pixel Conundrum
Another area to consider is the number of megapixels. A normal photo of a decent quality, for use as a screensaver or a slideshow for example, is fine at around 6 megapixels, or even less. This means that 6 million pixels, or little dots come together to make the image. If you want to create larger images, such as posters, or take photos that can be entered into competitions or submitted to magazines, then you should probably be looking at a model with a minimum of 8 megapixels. The very top cameras now have in excess of 20 megapixels, but this is not neccesary for your average photographer.
As an underwater photographer, you should also be a little wary of tiny cameras with a large number of megapixels. While these may be great cameras on land, they have a tendency to get hotter than larget cameras as the elctronics are crammed together, increasing the chances of fogging underwater.
Function over Form
In addition to the size of the images, the functions available to you on a specific model are very important for underwater photography. The ability to manually set the white balance is extremely useful. Setting the white balance, quite simply, means telling the camera what colour is white in different lighting conditions. Once the camera knows this, then it can adjust its balance so that all your colours look great.
Macro photography is also very popular among divers as small critters make fascinating subjects. If you think you would like to have a go at some macro subjects, it’s very useful to have a camera that has a small minimum focus distance & will allow you to focus manually. A good minimum focus distance for underwater is around 2 - 5cm.
Prior to sonar, anglers were totally dependent on their imaginations, and unless they were also divers, never really knew if their imagination matched reality or not. There is no substitute for the ability to see under the water. When you’re dragging your bait along a rough bottom, you might assume the bumps to be rocks, but it might actually be clamshells or ridges of sand. Sonar can provide a representation of structure, but not an actual image.
While ice fishermen readily recognized the value of being able to see what was going on underneath a hole, when underwater cameras came on the scene many boating anglers viewed them with a jaundice eye, unsure what useful purpose they might serve. For ice fishermen it's a natural. You can use the camera, pointed straight at your lure to see how fish relate to it, and how they react to various techniques. It is also a slam-dunk for delicate bites, enabling a visual hook-set on takes that might not be felt.
Now that some time has elapsed and the inventive spirit of anglers has had some time to develop techniques for open water, underwater cameras have opened up many possibilities that contribute to increased catches in soft water as well. In open water, the main use of an underwater camera is examining structure and confirming the identity of pixilated sonar images.
In addition to anglers developing useful techniques for this technology, since they were first introduced, underwater cameras have gone through significant improvements. If you've looked at them before, and decided to wait until they were refined, now's the time to revisit the issue.
First and foremost, water clarity is absolutely critical to successful use of an underwater camera. The ultimate environment for underwater cameras is during the winter, when lakes are covered with ice that prohibits wave action, which stirs up particulate matter in the water and diminishes camera performance. In a nutshell, you can't see through muddy water, at least not very far. When spring rains and algae blooms start to cloud waters in the southern tier of the nation, cameras become very limited. However, the northern tier of lakes and reservoirs that have much clearer water are much more underwater image friendly.
Unlike film or digital cameras, with underwater cameras lens aperture isn't an issue. Viewing angle is more relevant, and most cameras have an angle of 90 to 92 degrees. This length of lens gives you an ideal compromise between wide coverage and image size. Any wider and the fish you see would be very small and appear distant, and a narrower field of view would keep you constantly swinging the camera for more coverage.
Two technical issues affect image clarity, and the most critical is a matched camera and monitor. Monitor resolution is measured in TV lines, and the more you have the sharper and clearer the image. When your unit's camera and monitor output are matched they will produce a better image. Conversely, having a high-resolution camera and a low-resolution monitor will produce a low-resolution image, no matter how good the signal is.
Low light capability is the other key issue that affects what you'll see topside. At dusk, dawn and during winter when a heavy blanket of snow covers the ice, ambient light is pretty scarce. During these critical viewing times, auxiliary light is mandatory, but which light works best?
While it is important to keep in mind that you're not filming an episode of Jacques Cousteau for the Discovery Channel, you need an image that at a minimum has discernable images. You want to see what the structure is like, and what fish are using it.
When buying a standard camcorder the typically advice is to look for a camera with a low LUX rating, but there is some ambiguity in that statement. There's not a simple explanation of LUX, and for underwater cameras, the real issue is the lighting source, since you will almost always have to use some type of illumination.
For this reason, underwater camera manufacturers have placed their development emphasis on their lighting source. Some cameras utilize infrared light because it is not visible to humans, and as far as anyone knows, not to fish either. While infrared doesn't spook fish, it just doesn't travel well in water. Aqua-Vu's latest contribution to the problem is a solution they call a Spectral Response (SR) lighting system. The SR system uses both red and blue lights, on a black and white camera to take advantage of both of the positive aspects of each color. It's Aqua-Vu's position that blue light travels farther underwater, and red light is more affective for close-up images.
MarCum technologies maintain that blue is a more effective color, use all Blue LED's in their VS 460 / 560 models. To some degree, color is an issue of personal preference that can be debated, but is difficult to prove since the fish aren't talking. Something that isn't arguable is the advantage of automatic 360-degree scanning. Until recent innovations, anglers had to lower their camera and manually twist the wire supporting the camera to rotate to a different quadrant. In addition to the demands of manually rotating the camera, when weights are added to counteract the current or drift speed, the combined weight creates a cumulative weariness of the hands, arms and shoulders. Now, two manufacturers have small motors that do the work for you.
The Atlantis panning model utilizes a sealed camera that rotates 320 degrees, with a light source surrounding the lens in a diving bell shaped housing. This design works well in stationary applications, but the design of the housing isn't very open-water friendly. The MarCum camera is hydrodynamically designed and can be towed in open water more effectively. The MarCum unit also rotates 360 degrees and uses a concept called Dark Water Technology. Basically the light source is elevated a couple of inches above and behind the lens to minimize the negative glare that is reflected directly back to the camera from floating debris in the water. This is a particularly troubling problem in open water, especially during warmer months when particulate matter is most prevalent.
The two models mentioned above hang their hat on the considerable advantage of a motorized rotating camera; however, Aqua-Vu has taken another approach aimed at stealth and deception, making their cameras to look just like colorful fish. The paintjob on these cameras is remarkable and would certainly fool fish into thinking one of their cousins was swimming by. In fact, they look so realistic that they might also prove effective at attracting large northern or muskie. Fortunately, this camera's Kevlar reinforced cable will help you wrestle it free should one take a nibble.
If you're a fan of home video, and want to have the footage to review or relive the moment that trophy committed to your lure, look for units with a video output jack. This feature is offered on more sophisticated units and can also be used to connect a larger monitor directly to the unit. You can even add a marine quality DVD unit, for serious recording.
Cables are available in lengths from 60 to 120 feet, with various reinforcing materials to give them more strength, should your camera become tangled or snagged in underwater hazards. You'll find everything from Kevlar to steel mesh and just plain video cable.
Speaking of cables, another advantage to the MarCum units is the ability to control the depth of the camera from the monitor. With their adjustable cable cleat you can regulate camera depth without taking your eyes off of the monitor.
Looking at the wide array of options in underwater cameras, it's easy to see that this technology has come a long way. If you've often wondered just what it looks like beneath the surface of your favorite fishing hole, now's the time to find out.