Sea&Sea has announced a universal housing for Sony Alpha series cameras. The MDX-au is currently compatible with the a7 Mark IV, a7R Mark IV, a7S Mark III, a9 Mark II, and a1, although there are modifications and limitations with some models (see below). The housing utilizes Sea&Sea’s MDX ports, and ships with a vacuum system, and there are a number of electronic and optical strobe triggering options available.
Sea&Sea MDX-αU Underwater Housing for Sony α1/α9II/α7sIII/α7RIV/α7IV
Universal compatibility with the Sony Alpha series. The future-oriented mirrorless SLR compatible housing is now fully loaded
Universal design for the future. The back panel is designed to be large.
The back acrylic panel is more than twice as large as before to improve the visibility of the monitor and reduce the underwater weight. Furthermore, it is a sustainable design that can be used with new cameras in the future with minimal parts replacement.
Newly designed fiber-optic cable cover Newly designed optical fiber cable cover.
Newly designed fiber-optic cable cover included. Prevents optical cable terminals from falling out and smartly protects light-emitting panels and cable terminals. Includes a strap to prevent loss of the cover.
Leak Alarm Unit as standard equipment
The Leak Alarm Unit, which was previously available as an option, is now included as standard equipment. It is effective not only for early detection of underwater flooding accidents but also for the protection of equipment by checking its waterproof performance before entry. CR2032 lithium battery included.
Strobe Synchro System
Three optional strobe connection methods are available.
Optical TTL connection
[Product No.50139] Optical YS Converter S1
Compatible with SEA&SEA “Optical YS Converter S1” which converts the strobe light emission signal of the camera to LED light and synchronizes with the SEA&SEA YS strobe. It is a high-performance converter that does not just emit simple light-emitting signals, but also performs TTL auto light control. *Sony original adapter “ADP-MAA” is required separately for connecting camera and optical YS converter.
Optical manual connection
[Product No.50146] Manual flash trigger
For those who do not need TTL photography, the fiber-optic cable connection enables manual firing of the YS strobe.
[Product No.50147] Strobe connector/N
[Product No.50122] Optional Sync Cord 2-pin Connector
YS strobes can be electrically connected with a sync cord.
Full range of standard equipment
Grip Plus made of silicone material
Robust yet secure fit to hold the housing in place
Lighting can be deployed as desired from the SA8 fixed ball base
Pre-equipped with lanyard hooks for convenient transportation
Functional Limitations and Enhancement Customization Kit
Common to all models
Up/down/left/right buttons on the multi selector cannot be used
Use the up/down/left/right buttons on the control wheel instead
The up/down/left/right buttons on the control wheel cannot be used to move the focus point
Focus point can be moved with the front and rear dials using the camera’s dial customization function
Drive mode/focus mode dials are not available as standard
It can be supported by using the optional kit
If you want to change the drive mode etc. without modification, you can temporarily use it by registering the camera’s custom shooting setting in advance and calling up the function, but it is not a perfect substitute
The shooting mode lever cannot be used
This can be handled by using an optional kit
S&Q cannot be used
[Product No.50148] α1 customize kit for MDX-αU
Compatible with drive mode dial/focus mode switching lever.
[Product No.50149] α9II Customize Kit for MDX-αU
Compatible with drive mode dial and focus mode selection lever.
[Product No.50150] α7IV Customize Kit for MDX-αU
Compatible with shooting mode selection lever.
MDX-αU Other Features
The Port Lock prevents the port from turning or loosening and the Port Lock lever is specifically located to avoid being unlocked accidentally
The housing is equipped with a lens-lock release button which makes it possible to change lenses easily, without opening the housing
Pulling out the Focus/Zoom Dial gives sufficient room inside the housing to easily accommodate larger diameter lenses
All controls have luminescence stickers that glow in a dark environment
Equipped with the Optical Viewfinder 0.5x as standard. Other optional viewfinders such as the VF180 1.2x, VF45 1.2x, and Optical Viewfinder 0.66x, 0.8x can be used
*Some vignetting occurs when the VF180 1.2x is mounted on the housing, the upper part of the camera’s viewfinder cannot be viewed due to vignetting
* Equipped with two sacrificial zinc diodes (one on the front case and the other on the rear) to prevent electrolysis damage
* Tripod screw mount is located on the center underside of the housing
* Equipped with under guard to protect from scratch
Body: corrosion-resistant aluminum alloy (machined)
Grip: corrosion-resistant die-cast aluminum alloy
100m / 330ft
330 x 169 x 137 mm / 12.9 x 6.6 x 5.4 inches
Approx. 2,900g / 102.3oz (Housing only)
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