Scuba Friendly pixels.

Ok, I’m out of my depth on this request. In theory I can offer my opinion on which camera is best suited to underwater photography, but in reality I haven’t scuba-dived since Oakley Frogskins were in fashion (the first time around), and I never used a camera underwater. So my following observations are purely theoretical.

I’m going to ignore the housing required for the camera at this time as each body will require a specific casing, and each casing is roughly the same cost for the same depth.

So how would I choose one body over another?
My understanding of underwater photography is the deeper you go the darker it gets… so high iso capabilities may be desirable. However this factor is quickly equalized with external lighting.

The next thing i’ve read is that depth of field is a important factor. In this case having more depth of field being a good thing.

Now, camera bodies… this gets tricky quickly… where to start. With such a huge array of candidates I’d easily get bogged down in the details. Fortunately I was asked to compare two specific cameras. The Canon 5Diii and the 7Dii.
Based on the technical specs:

Advantages of the 5Diii

  • LARGER SENSOR 35MM vs APS-C Bigger is (generally) better.
  • 23 megapixel sensor (vs 20.2)
  • BIGGER PIXELS ~ 6.25 vs 4.11 MICRONS Better low-light and dynamic range (all else equal)
  • HIGHER EFFECTIVE ISO 2,293 vs 1,082 ISO
  • MORE VIEWFINDER MAGNIFICATION 0.71X vs 0.63X Get a bigger view of the scene through the eye-level viewfinder
  • LARGER LCD  3.2″ vs 3.0″ screen
  • LESS SHUTTER LAG 0.12 vs 0.25 s
  • HIGHER EXTENDED ISO 102400 vs 51200 ISO (but at that ISO it’s all crap)

Advantages of the Canon 7Dii

  • LESS EXPENSIVE
  • BUILT-IN GPS
    Geotag your photos
  • ON-SENSOR PHASE DETECT
    Usually improves live view and video AF performance
  • MORE CROSS-TYPE AF POINTS 65 vs 41
    Cross-type AF points improve autofocus performance
  • BIGGER JPEG BUFFER 103 vs 63 SHOTS
  • FASTER JPEG SHOOTING 10 FPS vs 6.0 FPS
  • BIGGER RAW BUFFER 26 vs 18 SHOTS
  • FASTER RAW SHOOTING 10 FPS vs 6.0 FPS
  • DUAL DIGIC 6 processors vs single Digic5+
  • Full HD 60p Video Recording
  • USB 3 connection for faster tethering
  • As a crop sensor Larger DOF for equivalent field of view.

Summing it all up? If autofocus is important to you in both still and movie mode the 7Dii is a winner. In my opinion it keeps up to the 5Diii in almost all aspects and has a couple advantages as well for underwater photography.

On land the 5Diii has a couple advantages- higher images quality and higher ISO. Which are ideal for family portraits and general all round use. But if you are not printing wall murals I don’t think you will miss the two extra megapixels.

If you are active and images include sports and wildlife I’d still choose the 7Dii . The camera body is also even more weather sealed making it a robust camera for hikes and getting dirty.

When asked for my opinion, I honestly thought I was going to recommend the 5Diii hands down. However, after reading a few blogs and factoring in some input from scuba sites, and looking at the data charts…

All factors considered, I’d say the Canon 7Dii would be my underwater choice.

Disclaimer – I have not used either camera underwater in their respective housings – things don’t always perform as advertised .