To begin this review, I have a confession. It is simple: I am a Nikon shooter. This is not due to any assumed superiority of the brand’s products but simply a historical quirk that has meant that I invested in Nikon first. I am currently shooting a Nikon D800 in a Nauticam NA-D800 housing and am continually amazed at how good a camera system it is. So then how might I review a Canon product objectively or thoroughly?

I was fortunate enough to be loaned a Canon EOS 6D in a Nauticam NA-6D housing, with a Canon 8-15mm lens and a Zen 4” dome with a removable shade. I took the whole lot away with me as my only SLR camera on the Wetpixel Ultimate Whale Shark expedition in late July, and must confess that I had some serious misgivings. Trips like this are (for me) events where I want to be happy with my camera’s performance and not be fighting with unfamiliar controls, settings and performance. I normally spend a great deal of time getting familiar with my cameras but time and equipment availability constraints meant that the first picture I would take with the rig would be in the water with the whale sharks. If I am honest, I downloaded the instruction manual onto my iPad and read it during the plane journey to Mexico so I would at least be able to control basics like aperture, shutter speed, ISO and autofocus (AF).

I am also always loath to dive a new housing (even with someone else’s camera and lens in it!) unless I am sure that it will not leak. I would normally do this by diving the housing without the camera at home prior to setting off on assignment However, the time limitations that I alluded to above meant that this was not a possibility. To cover this I fitted a Backscatter Airlock to the housing’s accessory port and relied on using it to show that the housing was holding a vacuum and hence unlikely to be leaking.

Whilst the camera and housing did get a “real world review”, being used for 6-7 hours a day in the sea, shooting images of marine life, it was not a comprehensive one. I shot the camera and housing without strobes, and with only one lens. If you are considering this combination, I have no experience of its suitability for macro photography, or for more conventional wide-angle photography.

Canon EOS 6D camera

Canon released the EOS 6D one week after the fanfare that surrounded the release of the Nikon D600. Perhaps due to this, it was not a camera that seems to have attracted much attention. Its specifications are good: It is equipped with a new full-frame 20.2 megapixel sensor and the same DIGIC 5+ image processor as that used on the EOS 5D Mk III and EOS 1D X cameras. The sensor features a native ISO range of 100-25600 and 1080 video at 29.97, 25 and 23.976 fps. It only has 11 focus points and although only the central one is cross-type (can detect vertical and horizontal detail), the AF works at very low light levels with a claimed sensitivity down to -3EV.

The 6D features integrated wi-fi and GPS, although neither are of much use inside a housing or underwater. I found that switching these off significantly extended the battery life, a more important factor considering I only had one battery! The battery is the ubiquitous LP-E6, as used in both 5D models as well the 7D and 60D. It gives a comfortable day’s shooting.

Canon users familiar with the EOS 60D will find the control placement on the 6D very similar. It offers the ability to move the autofocus actuation control from the shutter release to the AF-ON button on the camera’s rear.

A common feature missing is a built in-flash. Many pro level camera bodies are not equipped with flashes as it is assumed that pro photographers will chose to use external flashes which are more powerful and controllable. In recent years, there has been a strong trend towards using fiber optic strobe triggering via a camera’s own flash. The lack of a built in flash forces underwater photographers to either use electronic strobe triggering or some form of flash trigger that can convert the camera’s hot shoe signal into a optical one.

The 6D has a comparatively slow maximum frame rate of 4.5 fps. Ordinarily, I would not see this as being too critical for underwater photography, but as I will discuss later, breath hold diving while shooting is perhaps one of the times when it is good to be able to shoot quickly.

Canon list the viewfinder area as 97% (0.71x), identical to that of the 5D Mark III. The Nikon D600/800 is very similar at 0.7x. Viewfinder specifications are notoriously difficult to interpret in lists of camera specifications as there is no universal standard. Suffice to say that the 6D’s is large, light and allows for very precise framing. The AF points seem quite clustered in the center of the frame, which gives AF coverage similar to that of the older 5D Mark II.

Perhaps in an attempt to differentiate this camera from its more expensive brethren, it only has a single SD card slot. It produces RAW files at around 20MB, and there are plenty of high capacity cards available, so there is no issue of capacity, but if you are planning to shoot both video and stills, I find the workflow easier if you can record to different cards. I used a 64GB Sandisk Extreme card and found that this gave more than enough capacity for a day’s shooting.

For a full synopsis of the camera from a surface photography standpoint, DPReview has published an excellent and comprehensive review.

Canon EF 8-15mm f/4L Fisheye USM lens

This lens is perhaps the best reason for Nikon underwater shooters to switch to Canon! It is a truly versatile lens that can be used with both full frame and cropped sensor cameras, is a part of Canon’s L series lenses and is robust and quick to focus. On the 6D, it goes from a full circular fisheye at the 8mm end, to a moderately rectilinear one at the 15mm. It is easy to draw comparison to the Tokina AT-X 10-17mm F3.5-4.5 DX. The latter is a DX (cropped sensor) lens which, whilst very useful underwater in terms of its focal length and zoom range, suffers with build and optical quality. My experience is that the Canon lens is optically superior and much better made. It should also be noted in terms of image quality that I used the 8-15mm on a full frame camera, and one would perhaps expect it to be higher.

1. Introduction, EOS 6D and EF 8-15mm f/4L Fisheye USM lens.
2. Nauticam NA-6D housing and Zen DP-100 port.
3. In use, conclusions and acknowledgments.