What makes a good photograph can be broken out into 2 main categories:
- the equipment
- your skills.
- the camera controls
- the focal length of your lenses
- the quality of your lenses (optical quality, speed of the lens)
- the availability of light in the scene
If your camera is strictly a point-and-shoot, there is very little you can do with such a camera underwater - it's akin to being a passenger in a car versus being the driver. Unfortunately, photography is an elitist's game, and you will need to invest some money in the game if you're going to play in any meaningful way.
The focal length of a lens dictates how close you can or need to get to your subject. On land, telephoto lens allow you to capture images that look closer than they really are; underwater, things work a bit differently. Water is highly light-absorbent, which means that in order to capture an image with any degree of clarity, we must get physically close to the subject. This calls for the opposite kind of lens; instead of telephoto lens, we need lenses with wider angles that will allow us to get close while still retaining a good range of view.
The optical quality of the lens you're using affects the sharpness of your images. A high-quality lens allows light to enter quickly and translates the image with as little distortion as possible. When you buy a lens, this is the f-stop of the lens itself at the limit of its focal range; for a prime lens, that's just a single number, but for a zoom lens, the f-stop is the fastest the lens will let in light at the longest focal length of the lens. When choosing a lens, buy a lens with as low an f-stop as you can afford. For example, a 50 mm lens might be offered at f1.4 or f1.8; the f1.4 lens is going to be faster and therefore better, but it will be the more expensive of the two options. Underwater, the speed of the lens is arguably even more important than on land: water sucks light, so we need lenses that let in as much light as quickly as possible for any given shutter speed.
Underwater, as it is on land, we have two possible sources of light: ambient light or artificial light. Ambient light is essentially sunlight, or whatever sunlight manages to penetrate at the depth where you're shooting. Artificial light comes from flash lights or strobe lights that we add to the scene. Below 30 feet, it is really hard to shoot using ambient light unless you're going for a silhouette shot where it's the contrast of light and dark you're seeking, rather than details. Below 30 feet, to shoot an image with any details, you will need an artificial light source to add brightness to the scene and to add colour to it.
Underwater, colour disappears fast. Red is the first colour you'll stop seeing, while the deeper you go, the greener or bluer things will appear:
- Red - 15ft
- orange - 25ft
- Yellow - 35-45ft
- Green - 70-75ft.
If you can't invest in artificial light sources, your photographic opportunities underwater will be limited.
- your diving skills
Without good buoyancy control, about the only thing you'll be able to capture is likely just a series of blurs. Buoyancy control means being able to get where you need to go to be in position to shoot a subject and to be able to stay in place long enough and still enough to be able to capture the image.
Being relaxed underwater will also affect your ability to capture good images because it affects your air consumption rate. Having to surface within 30 minutes of a dive is going to cramp your underwater photography style.
Patience is our response to time and perhaps the most important contributing factor to a good underwater photograph, and the one that is the most difficult to cultivate if you're a naturally impatient person. Just because you're there at this red hot second doesn't mean the marine life should plan on cooperating. Just because you're on a mission to shoot a trumpet fish doesn't mean that the trumpet fish is going to be where it should be.
Time is also about opportunities and timing. On my fabulous trip to Wakatobi last summer, my goal was to capture pygmy seahorses. As you can see from my photograph below, I managed to capture a seahorse image, but I wouldn't call it a good shot because the seahorse wasn't looking into my camera. Compare my shot with the shot immediately below, taken by my brother after spending nearly 30 minutes with the creature.
I would argue that my brother's photograph is superior because he was able to spend more time with his seahorse and was rewarded with the money shot. And he also lucked out with his seahorse, who happened to be pregnant, as you can see from that distended belly!
You've no doubt heard of the rule of thirds for gas management - goodness knows we preach enough about it on this blog. Turns out the rule of thirds also works pretty well for photography. For any given compositional frame, the rule of thirds references an imaginary grid that divides the frame into a grid of three intersecting lines. In the simplest terms, the rule of thirds is an observation that when positioning a subject in a frame, the human eye perceives the image as being most pleasing when the subject is centred on the spots where the grid lines intersect, rather than smack in the middle of the frame. There are many, many examples on the Internet: search "rule of thirds", and you could be forgiven for thinking that surely there are fewer kitten pictures on the internet than the links to pages about the rule of thirds.
Tip: depending on your shooting situation, you may not need to worry too much about composing the perfect shot if you can't get into position for it. It IS possible to crop the shot for a better composition in post-production. The key is to have as much image of the subject to work with as possible to give you flexibility in post.
Beyond the rule of thirds, the most important consideration for composition is to remember that a photograph should tell a story. Unless the shot you're after is a catalog shot for a marine life identification book, you're going to want to think about the subject you're shooting: what do you find interesting about that subject? Is it the eye? Or the way the mouth on that fish reminds you of someone you know? A good photograph is not just a snap shot.
Veni. Vidi. Vici. "I came, I saw, I conquered." Julius Caesar supposedly said this about one of his short wars.
To create good underwater photographs, you'll have to go beyond the veni-vidi-vici approach. Underwater photography is a multi-dimensional craft that requires a magical combination of the right equipment, the right skills, and being in the right place at the right time.