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Sexton Photographics has manufactured custom underwater housings for cameras and other equipment since 1968. We only custom-build housings for cameras and other equipment. We do not stock finished housings, nor do we have standard designs to fit certain cameras. We do not compete with the manufacturers of stock housings.
If you can find a stock housing that meets your needs, buy
it. The stock manufacturers do a good job making housings to fit certain cameras. The R&D and tooling costs needed to manufacture those products have to be spread over many sales, so they target only a few very popular cameras. A hand-made custom housing from Sexton Photographics will always be more expensive than a mass-produced stock housing.
Sexton Photographics has a different philosophy that complements, rather than competes with stock housings. We only design and build housings for cameras or configurations that the stock manufacturers choose not to address. There are no model numbers, specifications, or brochures. The only photos available are those on this web page.
A custom housing may be the only way to take a favorite camera underwater. For example, there is no stock housing for the Kodak Stereo camera.
We had a customer who needed one, so we designed and built it, letting him explore his unique kind of underwater photography. A custom housing may provide a configuration that a stock housing cannot provide. For instance, a customer needed a very lightweight housing for a Canon AE-1 for surfing photography.
 While several stock housings were available for that camera, all were designed for underwater use, making them heavy and unsuitable for holding the camera up out of the water while swimming. We created a lightweight but strong housing, with features like handles on one side and on the bottom, to make the transition from horizontal to vertical format very easy. We clustered the main controls under the handles, and made the housing buoyant.
One of the advantages of adding a housing to a camera is that you can have the best camera for your purpose, by adding the best lenses and accessories for each task. You can customize your system to meet your needs, not just be stuck with what someone else decided they wanted to manufacture and sell. Similarly, an important advantage of a custom housing, rather than a stock housing, is the human engineering. Controls can be placed where you want them, rather than where they are most convenient for the manufacturer. You can pick features limited only by your imagination and the abilities and experience of the person designing the housing. You can have handles sculpted to fit your hands, and sized to fit your hands, if your hands are particularly large or small or gloved. You can pick the colors of knobs and handles. You can add specialized accessories if you need to. Look at the examples on this web page. All were designed to meet needs not addressed in stock housings.
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The larger the housing is, the more water it will displace. That means that a housing that is relatively large for its camera will be more buoyant that a tighter-fitting housing. You can add weight to offset the buoyancy, but remember that you have to carry all of that additional weight out of the water, too. One of the advantages of custom housings is that they can be designed to fit the camera as tightly as possible, leaving just enough room for the controls.
Some manufacturers of stock housings try to fit other cameras into their housings. Since the cost of tooling for each housing model is very high, they only design housings to fit the most popular cameras. With a small set of housings to choose from, they have to pick the next larger size to accommodate your camera, resulting in wasted volume, and more weight. Think of both size and weight when you are transporting the housing in a protective box, along with the rest of your gear, to and from your dive site.
A lot of work is done with wide-angle lenses underwater, so that you can get closer to a large subject and have less “gorp” (fine particles suspended in the water) in the water between the camera and the subject. Dome ports are often used with wide-angle lenses to minimize distortion, maintain the inherent angle of view, and increase color saturation. With a dome port, you may need a close-up adapter to focus on a small close virtual image, rather than the real object. Some autofocus systems do not work in that setup. If your need is primarily close-up and macro work, then a macro lens and a flat port work fine.
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 Be careful when choosing an autofocus camera for underwater use - there are different technologies, and some methods work underwater better than others. Depending on how the autofocus system is designed, it may not work underwater at all. You may have to use a control for the manual focus override, or pre-set the manual focus for the kind of subjects you anticipate for the dive. Sexton Photographics has developed a testing tank that can verify whether a particular camera can accurately focus underwater, either through a flat port or a dome. Rather than taking a chance, we can verify whether a camera unknown to us will work.
The test tank has a mount for a camera that lets it see through a dome port or flat port into a trough of water four feet long. A test subject is suspended in the water at varying distances from the camera, and actual exposures are made on film or digital media to test for proper focus. Here a Canon 10D and EF 20/2.8 lens are being tested with a 4 inch dome port.
 The
photo to the left is a photo taken with the setup above. The target, a colorful coffee cup, is at a distance of 25 inches from the film plane. The image in the middle is the clearly-focused target, while the other images are internal reflections from the walls of the tank and the surface of the water. While the reflections might be interesting, they are of no value in this test.
Many cameras these days have a built-in flash. Often this flash is very close to the lens, which will have the effect of front lighting every particle in the water. Unless you confine your diving to gin-clear waters, you will light up all the "gorp" in the water, a detriment to fine quality photos. In addition, the use of a flash inside the same housing as the camera lights up the inside of the housing and usually adds glare to the image, as well as confusing the autoexposure and autofocus systems. If there is no provision for use of an external flash, one method is to use a slave. One can shield the flash inside the housing, letting its light only fall on a sensor, which can then be used to trigger an external flash.
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The most common method of lighting underwater subjects is to have a strobe in a separate housing. The external flash can then be placed away from the lens axis, closer to the subject. There are several advantages to this technique. First, the subject’s features will often be shown in higher contrast and definition than if it was lighted flat from the front. Second, by lighting just the subject and not all of the particles of debris floating in the water between the camera and the subject, a clearer image is obtained. Third, since water absorbs colors from the light, a shorter light path will result in greater color saturation, and less shift to blue. It is not uncommon to use multiple strobes in external housings to achieve studio-quality lighting underwater.
One of the really great improvements in strobes, especially for macro work, is TTL (Through The Lens) flash. The flash system measures the amount of light (ambient + flash) coming through the lens, and quenches the flash at the right time for proper exposure, regardless of filters, magnification, and other losses. Several modern cameras have flash systems with this feature, and there are flash manufacturers like Sun, which make TTL flash systems for certain other cameras. These are known as dedicated TTL systems.
An example of this method is shown on the Olympus OM-2 housing, with a separate housing for the TTL strobe. The wired connection between the camera and strobe allows the camera to sense the amount of light at the film plane, and sends a signal to the strobe to quench it at just the right moment for proper exposure.
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Without TTL, another method of determining flash exposure is the use of a remote sensor. The purpose of the remote sensor (on strobes employing this light measurement technique) is to measure light reflected from the subject as the camera sees it. If a strobe with only its built-in sensor is mounted off-camera, it can only measure the light reflected back to it from the subject. As you move the strobe further off-axis, the difference between what the flash-mounted sensor and camera-mounted sensor sees increases. This is especially important underwater, where you often try to side- or top-light a subject to avoid also lighting the junk in the water between the camera and the subject. The remote sensor can be mounted inside the housing, where it can see what the camera sees.
In this case the remote sensor is the black object that says
Strobo-Eye.
The remote sensor is often mounted in a separate housing, so it can be aimed at the subject, especially for macro work.
Here, the remote sensor is mounted in the smallest housing on a mount that can be tilted and aimed at a close subject.
See the Minolta SRT-101 housing below.
Minolta SRT-101, 50/2.8 Vivitar Macro lens, Vivitar 929 strobe, and Vivitar RS-1 remote sensor.
The strobe housing is on a gooseneck for sidelighting the subject and minimizing the lighting of the junk floating in the water.
Thorough soaking and rinsing in fresh water is the first step. Then dry the housing with a soft towel before opening it. Maintenance of the o-ring seals is the most important part of keeping the housing free of leaks. In a clean, dry environment, the o-rings on access doors should be removed, cleaned, inspected, and lubricated before every dive. The o-rings around control shafts should be removed, cleaned, inspected, and lubricated annually. It is not uncommon for these o-rings to last twenty years, with proper care. A custom written
Owner’s Manual with detailed maintenance instructions, and a spares kit with silicone grease, and spare o-rings are included with every housing.
All materials used in our housings are well-suited for use in seawater. The housings are made of acrylic or polycarbonate plastic, the hardware is stainless steel, and the o-ring seals are made of buna-n synthetic rubber.
Acrylic (Plexiglas, Lucite, Perspex, and other trade names) is available in several grades, most of which are unsuitable for use in underwater housings. We use only the top grades of cell cast acrylics. Acrylic is the best choice for optical surfaces, and the preferred choice for housings. It is easy to cut, machine, polish, and bond.
Polycarbonate (Lexan, Tuffak, and other trade names) is a fairly clear plastic that is much more resistant to breakage than acrylic. It has a slightly bluish cast to it, making it generally unsuitable for lens ports. It is also much more expensive and more difficult to machine, sand, polish, and bond. Finally, it is also very unforgiving to spilled solvents, both in the shop and in the field.
Some deep water housings are made of aluminum. There are many grades of aluminum, but usually 6061-T6 will be the most suitable. This material is available in rod, tube, and sheet form.
All Sexton Photographics housings are designed with a conservative safety margin for implosion depth. We test-dive every housing in a pool (without your camera!) before shipment. The most common failure mode of underwater housings is leakage. Leakage can occur through a failed seal any time there is a difference in pressure between the inside and the outside of the housing. The pressure difference of only a few inches of water depth is enough to cause such leakage. Pool testing in a few feet of water is sufficient to thoroughly test the seals.
All housings are warranted for one year, as long as they have not been abused, modified, or exposed to depths in excess of the design
depth.
PLEASE CLICK HERE FOR THE FULL WARRANTY.
A compromised seal can flood any well-designed underwater housing. We cannot warrantee any housing against leak damage to your camera or instrument, because we cannot control your care and diligence in maintaining the o-rings.
You are encouraged to purchase flood insurance to cover your equipment. You may check with your insurance agent to see if your homeowners or renters policy will already cover this, although that is unusual. You may be able to add a schedule of your items to an addendum to your existing policy, or you may explore taking out a separate inland-marine all-risk policy to cover flooding of your equipment. You may also consider purchasing dive equipment-specific insurance, from such organizations as
DEPP
or DAN/H2O.
You are also encouraged to purchase coverage on the housing itself, since the exact model of your camera or equipment may not be available for replacement from a future loss, and the housing will not necessarily fit a new model.
Please visit our ordering section
for an overview of our work process and what to expect. ^Top
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