Sony Alpha a7 IV underwater housing byMarelux

It's been three years since the release of the Sony α7III full-frame mirrorless camera and the followup α7IV delivers many of the new features we've seen in other models packaged into this true hybrid imaging system.  A new high-resolution 33MP BSI sensor powered by the BIONZ XR processor delivers 4k60p internal capture without crop in 4:2:2 10-bit 600Mbps quality or 30p downsampled from the full 7K sensor width.  Paired with massively improved autofocus, 15+ stops of dynamic range and new Active Mode 5-axis stabilization makes this a powerful high resolution photo and video platform worthy of the α7 badging. THE SONY ALPHA 7 Mark IV Camera The Sony α7 line of full-frame mirrorless cameras has long been at the forefront of offering a variety of models with similar form factor that are geared towards different shooting styles.  With the α7 RIII and RIV, the focus was on low-light video-centric and ultra high resolution respectively while the α7IV marries the two to create a true hybrid shooting platform.  The Exmor R backside-illuminated 33MP full-frame sensor delivers high resolution still photos while leveraging the large sensor size to provide ultra-sharp and color-rich video downsampled from the full 7K sensor width. Camera Specs 33MP full-frame Exmor R™ BSI CMOS sensor with BIONZ XR™ processor 4K 60p 10-bit 4:2:2 video without crop 4K 30p 10-bit 4:2:2 downsampled from full sensor width 7K w/o pixel binning Real-time Eye-AF for humans and animals S-Log3 gamma for maximum Dyanmic Range capture 5-axis in-body image stabilization AUTOFOCUS The α7IV's improved autofocus system borrows heavily from Sony's other α series releases of late using their Fast Hybrid AF system which combines phase-detection and contrast-detection to provide fast and accurate focus.  The AF area is expanded to cover almost 94% of the frame with 759 AF-points.  Sony's latest Real Time Tracking and Eye AF modes promise to provide both accurate focus tracking for stills and video.  A new Focus Map feature allows for easier visualization of depth of field when filming. to help insure the critical parts of your subject are sharp. 4K VIDEO 4K 60p video captured with 10-bit 4:2:2 quality at up yo 600Mbps without crop sets the α7IV squarely with its peers in video capabilities.  Adding in the option to capture 30p downsampled from the full 7K sensor width gives the user the option to choose the right mode for their shooting style.  Capturing video in the S-Log3 gamma profile gives access to the camera's full 15+ stops of dynamic range for increased latitude in post processing. IMPROVED CONTROLS In addition to upgrading the autofocus, video and still capture  capabilities of the camera, the α7IV also now has the option to maintain discrete settings for video and still modes.  The dedicated dial atop the camera makes switching between modes hassle free.  The menu system has also been upgraded to make navigation easier and more similar to other recent models. NAUTICAM NA-A7IV UNDERWATER HOUSING The NA-A7IV underwater housing by Nauticam is designed as an optimized solution for both underwater still and moving image capture.  Outfitted with Nauticam's extensive lineup of accessories, the NA-A7IV can be customized to excel in either role.  The latest in a long lineup of Sony mirrorless system housings, the NA-A7IV features the same intuitively placed controls, easy setup, and rugged reliability user's have come to expect. MISSION CONTROL Never miss a shot looking for a button or dial.  Regardless of where the control may be found on the camera, Nauticam engineers have placed that control on the housing where it is needed most.  Essential dials and buttons are within easy reach of the reinforced ergonomic handles.  Atop the housing, a new dedicated lever allows quick switching between Still, Movie and S&Q (VFR Video) modes.  A dual thumb lever near the right handle actuates the REC and AF-ON buttons and a single lever near the left handle is for PLAYBACK.   HDMI 2.0 A large bore M24 bulkhead is located at the front of the housing for use with HDMI 2.0 or HDMI 1.4 (with a step-down adapter to M16) external monitors and recorders.  An additional M10 threaded mounting position near the front center of the housing also makes using an external monitor even easier.  The A7IV can output 4:2:2 10-bit 4K at up to 60fps to external recorders allowing for recording in edit-friendly codecs such as ProRes.  See the resources sidebar for additional details and recommended setups. PREMIUM PROFESSIONAL OPTICS Built around the N100 Port System for Sony E-Mount, the NA-A7IV can support a wide variety of native lenses with a selection of Optical Glass and Acrylic ports.  When used with an E-Mount to EF-mount lens adapter and an N100 to N120 adapter (see Resources sidebar for supported adapters), the NA-A7IV can be used with the Canon N120 EF-Mount port system, expanding the capabilities of the system even further.  Going beyond conventional optics the NA-A7IV can leverage the unparalleled optical quality of Nauticam's Water Contact optics such as the WACP-1 which offers up to 130º field-of-view, full zoom through, an almost 0" minimum focus distance with supported lenses.  For macro, the SMC-1 and SMC-2 deliver tack-sharp super-macro magnification levels up to 4x with the Sony 90mm macro lens. VACUUM CHECK AND LEAK DETECTION The housing comes with electronics pre-installed for Nauticam's Vacuum Check and Leak Detection system, requiring only the optional M14 Vacuum Valve (25624). This monitoring system provides constant updates on the water tight and safe-to-dive status of the housing. A simple color coded LED lighting system lets the user know that the vacuum is solid, or that the housing is losing vacuum. Leak detection is built into the same circuit, so if there is water intrusion, an audible and visual indication will occur. The Nauticam system is temperature compensated, eliminating false alarms caused by a change in outside temperature, or from a camera heating up on an action packed dive. STROBE TRIGGERING Triggering of external strobes is accomplished via the integrated fiber-optic bulkheads when using the optional Mini Flash Trigger for Sony (26302).  Electronic triggering is also via an optional Nikonos Bulkhead.  Note that when using this with the Vacuum Valve will require the optional M14 Offset Connector with Vacuum Valve II (25026).