Today I’m going back to one of the basics topics in underwater photography, wide angle lenses.
One of the most repeated sentences when coaching underwater photographers is “get closer” and there is a very simple reason. Water will absorb and dissipate light causing the image quality and contrast to rapidly drop, therefore, the further away the subject is, the poorer the image will be. This problem is dramatically increased if the conditions are not optimal, sediment, sand or plankton in the water will rapidly reduce the image quality.
In order to regain the sharpness and contrast we want in our pictures, the only solution is to get as close as possible minimizing the water column between the lens and the subject we are photographing. And here is where the wide angle lens comes into play.
A wide-angle lens in land photography is considered any lens with a focal length shorter than 35mm (or equivalent depending on your camera). The shorter the focal length is, the greater the angle of view of your picture.
By increasing the angle of view of your camera you will be able to reframe your picture from a shorter distance.
Another reason to get closer to your subject is to ensure the light of your strobes reaches the intended areas. Even the most powerful flashguns have a working distance of no more than 2 meters.
Wide angle options
When looking at wide angle options you have two main groups. Fish-eye and rectilinear.
Fisheye lenses have a greater angle of view, most of them can give you up to 180 degrees of diagonal coverage. This means that the camera will capture an image covering 180 degrees of view from one corner of the frame to the opposite corner. To achieve this the lens will distort the image giving it a characteristic “Fish Eye” effect, hence the name.
These lenses are an excellent option for underwater, will allow you to focus incredibly close to your subject and maintain image sharpness all across the frame as well as offering a superb depth of field (the area of the image in focus from the foreground to the background)
Fish-eye is my first choice for wreck and general wide angle photography.
Rectilineal lenses do not offer the same angle of view however they do not create the same level of distortion. The depth of field is not as good as what a fish-eye lens offers but good enough so you can have a good level of flexibility.
A couple of things worth mentioning here is the corner sharpness and the ability to focus close to the camera. Rectilineal lenses can suffer from softens in the corners of the frame, particularly when shutting at wide apertures and if the dome port is not correctly positioned.
Because the way the optics work, rectilinear lenses will struggle to focus when a subject is very close to the dome. This will limit their ability to shoot close focus wide angle images.
There is one situation in particular when these lenses are by far the best option. Shutting sharks and other pelagic animals. These are generally speaking very shy rarely come close enough to use a fish-eye lens, the massive field of view will make impossible to fill the frame with your subject. The narrower view of rectilinear wide angle is much better suited to photograph these subjects.
For my next Shark Quest Photography trip to the Southern Red Sea, I will pack a rectilinear zoom lens. This will give me the ability to zoom in to fill the frame even when the sharks decide to maintain a cautious distance.
Prime or zoom lenses
You may have heard photographers talking about Prime and zoom lenses. The difference between this two kind of lenses is simple, prime lenses have a fix-focal length while zoom ones allow you to vary it. This means prime lenses have less optical elements, therefore, the image quality is less compromised and produce sharper images. This distinction applies to all lenses, not only wide angle.
Saying this, the image quality of modern lenses, even zoom ones is remarkably good and many photographers, including myself, are very happy with the results.
What about if I use a compact camera?
For compact cameras users, the options of fish-eye and wide angle are more limited but none the less available. There are many manufacturers that make conversion wet lenses. This lenses attach to the housing in front of the lens and increase de angle of view of the camera lens. These lenses are not cheap and as is the case with DSLR and Mirrorless cameras, the more you are willing to spend, the better the image quality will be.
Most wet lenses are designed to work with the camera lens set to a specific focal length. usually 28mm or equivalent. Even if you can zoom your camera, I would strongly advise against. The image quality, especially in the edges of the picture will be literally destroyed.
Recently some manufacturers came up with a wet wide angle lens for compact and mirrorless cameras that offers an incredibly wide field of view and allow full zooming capabilities. This is an excellent option for shutting pelagics such as hammerheads.
Join me on my next trip to the Red Sea, the Shark Quest Photography onboard the recently refurbished Hurricane. As part of the workshop, I will be talking a bit more in-depth about wide angle lenses options and if It is possible you are more than welcome to try one of my lenses.