The advent of cameras featuring SLR sized sensors, but with electronic viewfinders and interchangeable lenses has got many people considering these as alternatives to SLRs for underwater photography. The idea of a compact sized camera with SLR image quality is an attractive one, especially in a world where airlines are being increasingly difficult about weight limits. Sales of such cameras have apparently outstripped sales of SLRs in the Far East in 2011, which would suggest that manufacturers may put more effort into developing new and sophisticated models in future.

One of the issues around this new genre is the lack of an accepted term to describe them. Different manufacturers use different terms, including mirrorless, micro 4/3s and EVIL (electronic viewfinder interchangeable lens). To ease confusion in this review, I aim to adopt the latter, as it describes the camera type, without a specific brand association.

Sony released the NEX-5n EVIL camera in August 2011. The camera was an attempt to deal with the shutter lag that marred the NEX-5 and to update the camera’s sensor. The NEX-5 featured a 14.2 megapixel sensor, native ISO of 12800, AVCHD 1080i video recording and a 25 point contrast AF system. By contrast, the NEX-5n has 16.1 megapixels, ISO of up to 25600, the AVCHD v.2 video codec offering 108060p/50p and an improved algorithm offering faster AF performance. In addition, shutter lag was substantially reduced:

“Responses are accelerated further by a release time lag of approx. 0.02 seconds: the fastest of any interchangeable lens camera in the world. This, combined with an improved AF algorithm which doubled the readout speed from the image sensor and more efficient image processing, results in an AF that is significantly faster than the current NEX-5 model.”

In terms of size, controls and layout, the two cameras were substantially the same, with the only mayor change being the addition of touch-screen controls to the NEX-5n. The manual controls are (on both cameras) a control wheel, with two soft keys, an on/off switch and a video record button. The NEX-5n has a review button adjacent to the record on/off.

These controls present some very interesting complications for housing designers. So far, none have decided to attempt the use of the touch-screen for controlling the camera underwater, but the existing control surfaces present real challenges, both for housing design and use underwater. Even on land, the controls are fairly fiddly and complicated and involve navigating menus even for fairly simple operations like changing ISO. There is custom setting available that allow buttons to have important functions assigned, and underwater it is essential to do so. Even so, exposure control in manual mode involves a button press (or two depending on the previous adjustment) and the control dial to be rotated. Doing so without removing the eye from the screen is not impossible, but certainly ranks as challenging!

The NEX-5n has a 3” (75mm) tilting LCD panel with 921,000-dot resolution which acts as both “live view” screen, viewfinder and review screen. The screen tilts through 90° from horizontal to vertical. There is an optional electronic XGA OLED Tru-Finder attachment that can be added into the cameras accessory port, however, this replaces the flash and so is of limited use underwater. I am also not aware of any housing manufacturers that allow for the EVF to be used within a housing.

The camera is supplied with a TTL enabled flash unit, that is activated by simply raising it. This gives good performance with TTL fiber optically triggered external strobes.

There is currently no option to attach an electronic strobe. The camera does feature an HDMI out, so it could be mated with an external monitor, however, to my knowledge this has not been incorporated into any housings. The bulk of the HDMI port tends to be too big to be incorporated into on small form factor housings.

Sony E mount lens choices for underwater use are somewhat limited, particularly for macro use. The kit lens is an 18-55mm f3.5-5.6 zoom (equivalent to 27-77mm on FX) and is quite capable underwater. Other useful lenses include the 16mm f2.8 (24mm) “pancake” wide-angle, which can have fisheye or ultra wide-angle adaptors added and the 30mm f3.5 macro lens. Adaptors are available to allow the use of Sony α mount lenses with the NEX cameras, as well as third-party adaptors for other lens types. The use of non-Sony E mount lenses underwater has not yet been adopted due to limitations in terms of AF performance and/or size when inserting into a housing.

My own observations whilst using the NEX-5n are that while it provides very good image quality, even at high ISOs, the form factor and controls do limit its potential. It is very feature rich and incorporates a slew of advanced capabilities, unlike anything I have experienced on a camera before. As a land camera I really enjoy the features and size, however, once housed and used underwater with even more limited access to controls, many of these features are inaccessible.

A key issue here is where this camera sits within camera taxonomy. EVIL cameras introduce a new genre of camera into what was previously a compact or SLR debate. I think that, for underwater use, the image quality of this camera is at the SLR standard, but the form factor and controls are similar to those on a compact and this steers me towards feeling that the NEX-5n is more a very high performance compact than an SLR competitor. Photographic creativity with this camera is limited not by the technology, but by the ability to access it.

I should also point out that this may not be the situation with all EVIL cameras, including some models available now and, inevitably, those that will be released in future. The key is to watch this space.

FTC disclosure: The NEX-5n camera and lenses used for these reviews were kindly supplied at a discounted rate by Reef Photo and Video.

Page 1: Introduction.
Page 2: 10 Bar housing.
Page 3: Nauticam NA-NEX5N housing.
Page 4: Aquatica AN-5N housing.