First Look Sony Alpha a6400 Underwater Housing

The Sony a6400 mirrorless camera is a welcome newcomer to the underwater scene. It borrows a fantastic autofocus system from the a9, the company's flagship full frame camera. Sony claims it to be World's fastest autofocus, with 425 phase-detect points and 'Real-time tracking' for moving subjects.

A 24 megapixel APS-C sensor is plenty of resolution for most applications and ideal for shooting macro underwater. Like the other cameras in the mirrorless line, it accepts the wide range of Sony E-mount lenses as well as Canon EF-mount lenses using the Metabones adapter.

LCD Tilt

The camera features a super-bright tilting 3" LCD screen which may be angled inside of the housing for a more comfortable view. This is particularly comfortable when shooting video - which you'll be doing a lot of due to the camera's fantastic 4K/30p capabilities with full pixel readout and no pixel binning.

It's not useful underwater, but the screen is 180º fully tilt-able outside of the housing for any mandatory selfies during your surface interval.

Ergonomics

Every control knob has an upgraded soft-touch feel which gives them a great tactile feel and extra grip for quick action. All rotating controls utilize a quad-seal design and direct drive operation, meaning they're both bulletproof and field serviceable. 

The most important controls in any quick action shooting scenario are shutter and AF/MF button. Both of these controls are accessed through the side of the housing with levers gently curved in opposite directions. This provides a super sensitive and comfortable trigger-type action between your thumb and forefinger when using back button focus (see housing instruction manual for camera set-up). Both controls are extendable for the perfect placement if using a tray and handle attached to the housing.

The video recording start/stop control is bright red anodized for no brainer operation when the action starts. Hard anodized aluminum pushbuttons are lightweight, smooth-acting, and resistant to salt build-up when rinsed properly. Control function symbols are laser engraved into the back of the housing for high visibility identification which is fade-proof and will never fall off. 

Confidence in construction

The signature clear view acrylic back provides instant visual feedback on the camera status and o-ring seal that no detector or alarm can match. Industrial grade, double passivated stainless steel locking lid snap closure is virtually fail-safe.

A 1/2" accessory port provides an attachment point for an optional vacuum system. A simple hand pump allows you to pull a vacuum on the housing to check for leaks prior to putting system in the water. Drawing a vacuum on the system also provides extra security at the surface of the water, especially important when using the housing in rough surf. See how it works here.

Unlike many vacuum valves out there today, the Ikelite valve is low profile so that it doesn't interfere with control operation or get caught on your gear.

The housing and back are fundamentally corrosion-proof, highly durable, and significantly lighter weight than aluminum.

True TTL strobe exposure

Any fiber optic strobe may be triggered off the camera's built-in flash using the fiber optic ports that come standard in the housing. An optional Ikelite ICS-5 bulkhead and TTL hotshoe provide communication directly with the camera for use with the DL2 DS Link Sony TTL Converter. 

The DL2 DS Link is faster, more accurate, and more reliable than fiber optic TTL triggers and it supports rear curtain sync. Unlike our previous Sony TTL systems, the DL2 allows you to switch quickly between TTL and manual strobe exposure with the touch of a button. A super-bright LED gives clear indication which mode you are in. The DL2 DS Link is powered by the strobe - not tiny hearing aid batteries - so you don't have to worry about running out of TTL juice halfway through your boat dives.

Using the DL2 DS Link improves strobe battery life, camera battery life, and recycle times because the camera's flash does not need to fire and the strobe is being fired at shorter, more accurate flash durations. See images taken with the DL2 and Sony A7R III camera here.

The DL2 is independently waterproof sealed and will carry with you to other Sony systems if you carry multiple camera bodies or choose to move into a full frame mirrorless camera.

Dry Lock Micro lens port system

The Dry Lock Micro (DLM) port system is a compact sized version of our super rugged DL port system. Dry Lock eliminates primary weakness of most waterproof housing designs: positioning of the o-ring on the lens port itself.

Attaching an o-ring to the lens port increases the chances of twisting and extrusion during assembly, and risks dropping water onto the camera sensor during disassembly and lens changes.

The Dry Lock design avoids these risks by positioning the o-ring on the housing's port mount. The o-ring is clearly visible and easy to maintain. Lens ports secure with three no-nonsense locking screws that could be easily replaced if necessary in a remote location.

The best lenses for underwater photography are supported with a range of flat and dome ports. See a full compatibility list here. We recommend investing in the best glass you can afford. A high quality lens behind an optical grade flat or dome port will provide stunning underwater image quality. And unlike dedicated underwater optics, a high quality Sony, Canon, or Sigma lens is useful when you get out of the water too.

Don't get fooled into lugging around a 5 lb glass dome port either- our custom, optical acrylic 8" diameter domes provide results that are identical to the naked eye at a small fraction of the packing weight.

A team to back you up

All Ikelite housings and strobes are designed and built in our sole facility in Indianapolis, IN, USA. Our average team member is a certified diver and has over 20 years of experience in underwater housing manufacturing and service. We're here for you whether you need advice on choosing your equipment, setting up your gear, getting the shot, or editing and post-production. And everything in between.

Conclusion

We think the Sony a6400 is a great choice for a mid-range mirrorless camera system that can shoot high resolution stills or 4K video. The 200DLM/A Underwater Housing for the Sony a6400 is optimized for creative control and expandable with a broad range of accessories.