Choosing an Underwater Housing for the Sony a7C II or a7CR

By Jean Rydberg

Sony offers two powerful options for shooters who are looking to downsize their equipment without settling for a smaller image sensor. The a7C II features a 33 megapixel full frame sensor, in-body image stabilization, and 4K Ultra HD video at up to 120 fps. Its sister camera, the a7CR, is a high resolution version for photographers who need the most flexibility with the ability to crop photos in post-production.

Both cameras are physically identical and can operate interchangeably within the same camera housing. Underwater shooters have a choice of two different camera housings for these models, the 200DL and the 200DLM/A models. Here we explain the differences between the two models to help you choose the housing that’s perfectly suited to your shooting preferences.
 

The size of the housing is defined by the size of the lens port opening. The larger DL port system (right) accommodates Sony's high-end professional lenses. The DLM port system (right) is "micro" sized.

Lens Support

The compact size of the 200DLM/A Underwater Housing is largely due to the smaller footprint of the DLM port mount. This port mount is optimized for simple and streamlined installation of compact mirrorless lenses. The smaller diameter of the DLM port system does prevent the use of some of the high-end professional grade Sony E-mount lenses.

For example, the excellent Sony FE 16-35mm f/2.8 GM is too large in diameter to operate in the smaller DLM port system. The smaller system does support the 16-35mm f/4 ZA OSS and f/4 PZ G lenses, among many others.

Lenses are one of the biggest and best investments you can make in your photography. The most important thing is to check the port charts to make sure that the lenses you plan to shoot are supported in the housing of your choice.

• View the Sony DL Port Chart
• View the Sony DLM/A Port Chart 

The zoom gears are adjusted using a large lobed knob on the side of the DL housing. The DLM housing zoom drive gear lives in the 6" Dome Port. 

Large 8” Diameter Dome Ports

If you enjoy shooting super wide lenses and split shots (half-in, half-out of the water), it’s worth noting that the DLM 8” Dome Port does not support zoom operation. If you plan to use a wide angle zoom lens with the 200DLM/A Underwater Housing, you will need to either use it at a fixed focal length behind the 8” Dome Port, or use a smaller diameter 6” Dome Port with Zoom.

The 200DL Underwater Housing supports zoom in both its full size and compact 8” dome port options.
 

The camera mount is discrete and can be left attached to the camera when doing battery changes or even when attaching it to a tripod. 

Camera Mount

Both housings include a small mount which attaches to the bottom of the camera and is used to install the camera in a fixed position inside of the housing. The camera mount is designed to be unobtrusive and can be left attached to your camera even when shooting on the surface. In fact there’s a 1/4-20 threaded hole on the bottom of it so that it can be attached directly to a tripod. Most importantly, this mount plate may be left attached when changing the camera’s battery pack.

Only the DL version has room for cabling.

Battery Life and USB-C Charging

The Sony a7C cameras provide good battery life which can easily get through many hundreds of shots over 3-4 dives per day without recharging. Shooting video will drain the battery more rapidly and we find that batteries need changing or charging after about 2 dives when shooting video.

The 200DL Underwater Housing supports the use of the optional USB-C Charging and Data Transfer Bulkhead. This revolutionary accessory can be installed in the M16 accessory port on top of the 200DL housing. Removing the waterproof cap exposes a USB-C port. Simply connect a compatible USB-C cable between the housing and your computer or camera charger. This cable can be used to both charge the camera and off-load your images and video onto your hard drive. When you’re done you only need to replace the waterproof cap and pull a vacuum on the system again. It’s an incredible time saver and a safe way to charge your system on the boat in between dives.

The 200DLM/A housing does not support use of the USB-C Charging & Data Transfer Bulkhead. Changing the battery in the 200DLM/A requires the removal of the camera body from the housing. Depending on your choice of lens, you may need to remove the lens and port before taking the camera body out.

It's fair to say our USB-C Charging & Data Transfer Bulkhead was revolutionary to the underwater photography industry. Spend more time shooting and editing, less time breaking down and re-assembling your system.

Size and Weight

If you’re considering a smaller full frame camera, it’s likely that you’re trying to downsize your system. The 200DLM/A Underwater Housing is designed to be the smallest and lightest possible for photographers looking for a compact travel system. The housing body is only 2.6 pounds (1.18 kilograms). The housing is form fitted to the camera body and slightly negatively buoyant. Actual buoyancy depends on the choice of lens and port.

The 200DL Underwater Housing is slightly larger to accommodate a wider variety of accessory connections and premium grade optics. The housing body weighs in at 4.6 pounds (2.1 kilograms) without the handle or port attached. The increased volume of the housing increases the buoyancy of the system and is neutral or slightly positive depending on your choice of lens and port. Positive buoyancy can be offset by either adding strobes or the optional Trim Weight System.

Checking for leaks prior to entering the water is good practice with any camera and housing system. Our vacuum valve is low profile and has no batteries to maintain.

Vacuum Leak Detection System

Most underwater photographers like to go into the water knowing that they have assembled their housing properly and will come up with a dry camera at the end of each dive. The best way to ensure this is using a vacuum leak detection system.

The 200DL housing includes a low profile vacuum test valve on the side of the housing. Use the optional Vacuum Pump with Gauge to pull a vacuum on the housing. If the housing holds a vacuum on the surface, chances are that you will not experience any problems at depth.

The 200DLM/A housing supports testing by adding the optional Vacuum Kit for 1/2” Accessory Ports. Check out this video to see how easy it is to install the vacuum valve in the 1/2-20 threaded port on the side of the housing.

Live view shooting saves battery life and can be easier on the eyes. If you need to use the camera's EVF, choose the DL housing.

Viewfinders

The a7C II and a7CR have large, easy to see LCD screens on the back which are perfect for composing and reviewing images underwater even in bright conditions. Both housings support the use of the rear LCD screen.

The cameras’ built-in electronic viewfinder (EVF) cannot be used for framing images inside of the 200DLM/A Underwater Housing.

The 200DL Underwater Housing includes our Super-Eye Magnifying Viewfinder which enhances your view of the camera’s EVF when viewing underwater through a dive mask. This housing supports the option to upgrade to either the Straight Magnifying Viewfinder or 45º Magnifying Viewfinder for larger, brighter, edge-to-edge viewing of the camera’s EVF. Not sure which one is right for you? Check out this article where we discuss the differences between Straight and 45º Magnifying Viewfinders.

Both housings come standard with an electrical bulkhead and manual hotshoe. You can add an optional TTL Converter, or swap it out for a Fiber Optic Transmitter.

Strobe Flash Support

Both housings support multiple flash triggering options. The a7C cameras do not have a built-in flash, so an external flash must be triggered through the electrical hotshoe on top of the camera.

Manual Flash with Electrical Cord

Each housing includes the reliable Ikelite waterproof bulkhead connection with a manual flash hotshoe. Use a compatible electrical sync cord to attach Ikelite or non-Ikelite strobes.

Automatic TTL Flash with Electrical Cord

TTL flash enables your camera to communicate with your strobes and vary the strobe power in response to the amount of light present in your scene. You can utilize TTL flash exposure with compatible Ikelite DS strobes by adding the optional DL2 DS Link TTL Converter and ST1 Hotshoe Kit.

Manual Flash with Fiber Optic Cord

Fiber optic strobes may be triggered by removing the electrical bulkhead and installing the optional Manual Fiber Optic Transmitter. Installation is simple and easy. The trigger provides two ports which accept Ikelite fiber optic cords or cords with a Sea&Sea-type connector. Strobe power is adjusted manually using the switches on the strobes. The Manual Fiber Optic Transmitter supports both Ikelite and non-Ikelite fiber optic strobes.

The DLM housing is so form-fit there's no room for USB or HDMI cabling.

HDMI Monitor Support

The much smaller 200DLM/A housing is so form-fit to the camera that there is no room to add auxiliary connections like USB, HDMI, etc. This prevents the use of external monitors.

The 200DL Underwater Housing allows room on the left side of the camera for auxiliary camera connections. The spare M16 threaded accessory port on the top of the housing can be used to attach a compatible third-party HDMI bulkhead. Additionally, the housing can be modified to add an M24 threaded accessory port on the left side for use with compatible HDMI 2.0 bulkheads.
 

The DLM housing (left; 2.6 lb) is about half the size and weight of the DL housing (right; 4.6 lb). Both housings accommodate both cameras interchangeably.

Summary

Sony’s a7C II and a7CR cameras are very powerful options for the underwater shooter. Choose the housing that best fits your shooting needs and travel restrictions.

The DLM/A underwater housing is a no-brainer for shooters who want to downsize their gear without sacrificing image quality. The housing is nearly half the size and weight compared to the DL version, which makes it easier to pack and carry around. Underwater, the system creates less drag, which is a relief when pushing through currents or kicking over long distances. But the decreased size also makes it less buoyant. So depending on your choice of lens and port you may need to compensate with buoyancy arms or floats.

If you also own a 2nd larger-body Sony full frame camera, then it would make a lot of sense to go with the DL housing. It shares the same ports and accessories with our housings for Sony’s professional cameras like the a7S III, a1, and a7R V. It also supports the USB-C Charging & Data Transfer Bulkhead which greatly reduces the amount of breakdown and assembly time you need to do over the course of a trip.

Both housings are highly functional and ergonomic options for these cameras. They are built here in the USA and each housing is checked with the cameras for proper functioning of the controls and electrical bulkhead. Each housing completes a water pressure testing cycle at shallow and deep depths up to 200 feet (60 meters) before it gets packaged for you.

Control access is the same between the two housings. 

Here’s a summary of the feature differences between the two models: 

	200DLM/A	200DL
USB/C Charging & Data Transfer	No	Yes
Support for Larger Lenses	No	Yes
Zoom with 8” Dome	No	Yes
Vacuum System	Optional	Built-in Valve
Weight	2.6 lb	4.6 lb
Viewfinder	Rear LCD Only	Built-in Viewfinder with optional Magnifying Viewfinders
HDMI Monitor	No	Includes M16 Accessory Port; Optional M24 Accessory Port Upgrade
Tray with Handles	Optional	Included Left Handle; Optional Right Handle
Trim Weight System	Optional	Optional
MSRP Housing Body	$1345	$1795
SKU	69124	71481
	See the 200DLM/A Housing	See the 200DL Housing

 

Still having trouble deciding? Have more questions? Reach out to us via ikelite@ikelite.com - we’re always happy to help.

 
 

Jean Rydberg, daughter of Ike Brigham, became President & CEO of Ikelite in 2006. Prior to that, she wisely pursued a degree in Astronomy & Astrophysics to prepare herself for the challenges of running a technology-driven manufacturing business with global distribution. Jean fully embraces the need to travel outside of her hometown of Indianapolis to experience good diving. She believes that any camera is capable of amazing results in the right hands, and anyone can become a great photographer given the right advice. When she's not working she's spending time with her husband, cats, and two daughters (though not necessarily in that order).

  

Additional Reading

DL2 DS Link Sony TTL Converter Underwater Photos

Never Take Your Camera Out of the Housing! // USB-C Charging & Data Transfer Bulkhead [VIDEO]

Large Bore M24 Port Modifications for HDMI Monitor Bulkheads

Straight vs 45 Degree Magnified Viewfinder for Underwater Shooting

Checking for Housing Leaks Using a Vacuum Pump and Valve