The Right Lens for Every Situation Underwater
By Jean Rydberg
There are hundreds of lenses available for DSLR and mirrorless cameras... Maybe you already own 5 or 6 of them. Or perhaps you're trying to decide which one to buy. Either way we can help distill it down to the right one for the shots you want.
At points in this article we refer to the camera's sensor size. The most common values in an interchangeable lens camera are (largest to smallest): Full Frame, APS-C, and Four Thirds. You need a lens that has the correct mount to attach to your camera (or a suitable adapter). If using a full frame camera, you also need to make sure you're using a full frame lens to avoid vignetting (portions of the frame blacked out by the lens body).
Four Thirds and APS-C are "cropped" sensors meaning they only represent a portion of a Full Frame sensor (which is the size of a film frame with a width of 35mm). When you use a full frame lens on a crop sensor camera you will only be capturing a portion of the lens' full field of view.
|Lens Manufacturer||Full Frame Lenses||APS-C Lenses|
|Canon||EF||EF-S or EF-M|
|Nikon||FX or Z||DX|
A macro lens and flat port are necessary when shooting tiny creatures like this Caribbean Sharpnose Puffer in Bonaire. You're not going to be able to get inches away from this guy so you need a macro lens with a decent working distance. Taken with the Nikkor 105mm Macro on a Nikon D850. Photo © 2020 John Brigham
All the Small Things
A macro lens in the 50mm to 60mm range is perfect for cropped sensor (APS-C and four-thirds) cameras. After the crop factor is applied these effectively act look like a 90mm or 100mm on a full frame camera. You can get as close as you want to your subject which can provide sharper images and more creative lighting possibilities.
The working distance for 50mm and 60mm lenses is too short for full frame cameras. That means you have to get too close to your subject to make it fill the frame, making lighting and control of your system more difficult. For full frame cameras choose a lens in the 90mm to 105mm range to work at a comfortable distance and still fill the frame.
Flat ports are used with macro lenses for several reasons:
- magnification of the subject;
- ability to add external wet lenses;
- ability to get closer to the subject;
- ability to get strobes closer to the subject;
- greater sharpness and less aberrations.
You can add one or more external wet macro lenses (diopters) to the front of your lens port to get closer and increase magnification for shooting super macro.
Super wide angle fisheyes are a joy to shoot on expansive reefs. Make sure to practice your close focus wide angle (CFWA) by positioning a subject in the foreground as close to your dome as possible. Taken with a Canon EOS 50D and Tokina 10-17mm Fisheye. Photo © 2020 Steve Miller
Reefscapes and Split Shots
These are the shots that give you the perspective of what it looks like to be underwater. Bright corals, fish life, and smooth water lines where the sky meets the sea. Our lens of choice is a super wide angle fisheye in the 8mm to 18mm range. These lenses give you a huge field of view and can focus right up to the front of the dome when shooting close focus wide angle (CFWA). Zooming into 15mm or so gives you some flexibility when your subject smaller or is a little farther away.
Dome ports are used with super wide angle and fisheye lenses for a few reasons:
- wider angle of coverage;
- no vignetting (where the port blackens the edges of the image);
- ability to shoot split shots.
The fins in this photo give a perspective of how much of a 251' (76.6m) wreck can be captured at close distance with a super wide 10mm lens. The fisheye distortion of the wreck's straight lines becomes more apparent the closer you get. A rectilinear lens like a 16-35mm will not be as wide but helps to maintain a normal perspective. Taken with a Canon Rebel SL3 and Tokina 10-17mm Fisheye. Photo © 2020 John Brigham
Wrecks, Models, and Big Animals
When shooting models in a pool or big animals and wreckage in the open you can reach for a lens with a little more reach, most commonly between 10mm and 50mm. A short range zoom provides the perfect amount of flexibility in both pools and open water environments, where edge softness is rarely a concern.
Rectilinear lenses are preferred over fisheye to help maintain straight lines and normal body proportions.
Dome ports are used with wide angle zoom lenses for all of the same reasons listed in the previous section.
Rectilinear lenses are most popular when shooting models but an 8-15mm Fisheye at 15mm will also do. Photo © 2020 Steve Miller
One Lens to Rule Them All
Wide angle wet lenses come and go, promising opportunities for both wide angle and super macro on the same dive. This prospect is very tempting, the thought that you will never miss any shot- just add or remove an underwater optic during your dive.
The reality is not quite so clear. High end water contact lenses can cost upwards of $7,500 and weigh over 15lb (7kg) to achieve a focal length range comparable to a fisheye zoom lens behind a dome port.
The funny thing is that sometimes a convenience can turn out to be more trouble than it's worth. You may find yourself fighting your system instead of focusing on improving your photography.
Go big or go home? A very wide lens and large dome port are essential when shooting split shots. When shooting big animals, consider how far you will be from the subject. If you're expecting to be mostly 10-15ft (3-5m) away, then you'll need a little reach in your lens. Try a wide angle zoom like a 16-35mm. Photo © 2020 Steve Miller
What Not to Shoot
Stay away from telephoto lenses with minimum focus distances of greater than 18" (0.5m) and lenses with longer zoom ranges of 18-105mm, 28-105mm, or greater. These lenses could be useful above the waves in surf photography but won't focus well underwater.
Stare at 100% crops of the corners of images and you'll start worrying about edge sharpness. Instead, try doing a Google image search for "best underwater photos" and notice that edges are not the focus of good composition. Soft focus, bokeh, and vignetting effects are commonplace in images that capture our wonder and imagination.
We advise against spending a lot of money to solve a problem that may not exist. Some lenses, particularly mid-range zoom lenses, do not perform well underwater behind a dome. All of the lenses referenced above provide excellent results when shooting with the recommended length of dome port. Set your aperture at f/8 or smaller, and start shooting.
Most underwater photographers can get through their whole careers with two lenses: one wide angle and one macro.
If great photos are you primary objective then we recommend investing in the highest quality wide angle or macro lens possible and shooting it behind the recommended port. And if you want more advice or reassurance on what system to dive in with, give us a call or shoot us an email today!
Jean Rydberg is the President & CEO of Ikelite. She has lived her whole life in landlocked Indianapolis, Indiana, but is no stranger to the water as a daughter of Ikelite’s founder Ike Brigham. She has traveled around the world shooting and testing gear and enjoys new challenges in both photography and diving. Jean loves to learn about the creative ways photographers achieve their visions. More than anything she wants to show aspiring underwater photographers that excellence is attainable with any system. When she's not working she's spending time with her husband and two daughters.