Choosing a new camera can really value add to your existing lenses and give them a new life.

The Olympus OM-D E-M1 Mark II Micro Four Thirds camera adds extra dimensions to your Micro Four Thirds kit by giving them even better image stabilisation, awesome C-AF at 18 fps burst rates with Pro-Capture option and the option of 50mp HiRes mode (albeit requiring a tripod and static scene).

Many of us have a collection of Canon pro lenses and an old Canon dSLR camera which needs updating to value add to these lenses – but which camera?

Sure, you could adapt them onto your Micro Four Thirds cameras but these Canon lenses are not optimised for CDAF, so you need an expensive Metabones adapter to get reasonable AF – and the capability will vary with each lens – some, such as the Canon EF 50mm f/1.8 II, Canon EF 100mm f/2.8 macro and one of my favorites, the Canon EF 135mm F2L lens will just not AF with a Metabones adapter – whether a straight adapter or a 0.71x focal reducer adapter.

You could buy a cropped sensor Canon dSLR, but unless you are into sports where the Canon 7D Mark II will be useful, the full frame lenses are just too big and poorly suited to cropped sensor dSLRs and Canon don’t make many pro quality lenses designed especially for their cropped sensor cameras.

If you have the money, the obvious choice are the superb Canon 1DX Mark II or the Canon 5D Mark IV but these are likely to break your bank at around $AU5000.

You see money is everything for most of us, if money was not an issue, we would probably buy a variety of best of breed cameras such as:

• Hasselblad or Phase One medium format for landscapes and studio work
• Nikon D5 or Canon 1DX with massive, expensive lenses such as a 600mm f/4 for sports or wildlife
• Olympus OM-D E-M1 Mark II for everyday use and compact, light travel

But money is an issue for most of us, and so in the Canon full frame dSLRs at the entry level end we have the outdated Canon 6D or Canon 5D Mark III dSLRs, but although these will get you the full frame shallow depth of field and high ISO capabilities, these are not suited to sports, have an old sensor which has less dynamic range capability at base ISO than even the E-M1 Mark II, and in the case of the 6D in particular, has crippled functionality such as a shutter speed only to 1/4000th sec.

Can we do better at an affordable price? – Enter the Sony a7II

The Sony a7 mark II combined with the relatively new and affordable  Sigma MC-11 Canon EF lens adapter may well be a better option than the similarly priced older canon 6D IF you can live with a few major issues:

• variable AF functionality depending upon the lens but unlike using the much more expensive Metabones adapter, the Sigma MC-11 adapter works really well with the Canon EF 135mm f/2L, so well, that it has made me consider the Sony a7II as a reasonable option! The Canon 50mm f/1.8 II works, but every time you turn the camera off and then on, the lens freezes, so you have to partly dismount the lens and mount, then turn camera back on to re-gain AF functionality.
• terrible ergonomics – I am not sure what happened to all those Minolta camera engineers when Sony took them over, but, the Sony cameras are certainly not designed with the photographer in mind – if you think the Olympus menu system is confused and convoluted, Sony is worse, and with sometimes very strange  design options, and worse, the constant need to dig into the menu system for simple things such as switching from back button AF to half shutter AF modes, and unlike the Olympus, navigating the panel display settings is very clunky, plus for some reason, the EVF looks blurry even after adjusting the diopter, and countless other annoyances such as no button to switch from EVF to screen manually – yep, you guessed it – another deep dive into the menu system – if you can remember which screen its on! Plus, unlike Olympus, there is no context-sensitive help on the menus or the Scene modes (you just get a sometimes obscure icon).
• did I mention terrible ergonomics?
• did I mention the really loud shutter? – unlike Olympus, there is no silent mode – but at least your subjects can hear you taking the shot from 10m away!
• cannot yet use Canon flashes in TTL mode – but they work fine in manual mode – thankfully, Sony got rid of the proprietary non-industry standard Minolta hotshoe! PS. the Cactus radio wireless TTL flash system is being updated in 2017 to allow Canon and Olympus flashes to work on Sony cameras and other brand cameras including Olympus cameras with full TTL remote radio wireless flash – but Sony and Pentax cameras currently require brand-specific flashes for HSS mode. AWESOME!
• is not supplied with an external battery charger – what the??? You charge the battery via USB cable with battery in the camera – not very useful if tyou want to use the camera while the battery is charging! You can apparently buy one with a spare battery for about $100

What benefits does the Sony a7 II have over the similarly priced Canon 6D?

• mirrorless – camera is smaller and lighter, 600g vs 770g
• EVF instead of OVF means you can hold the camera to your eye for Live View including movies, plus, if you are like me and require reading glasses, you can get away without them by using the EVF for everything including diving into the menu
• manual focus magnification with focus peaking in the viewfinder – fantastic for Tilt-Shift lenses which are otherwise difficult to focus
• ability to use native Sony lenses as well as Leica M lenses – probably not a big deal unless you really want to invest in an essentially flawed design system -in my opinion, Sony made a mistake in designing the E-Mount sensor to lens flange distance so short and the mount diameter so narrow – sure it makes the cameras smaller, but that doesn’t help much on full frame as the lenses are gigantic, and furthermore, it cripples image quality with wide aperture, wide angle lenses and cripples the capabilities of a sensor based image stabilisation system – hence the Sony Steady shot IS is no match for the Olympus system, and according to the laws of physics is unlikely to ever be!
• 24mp newer sensor with much better dynamic range compared to the old 2012 model 20mp sensor of the 6D
• shutter speed to 1/8000th sec not just 1/4000th sec
• 5 axis sensor based image stabiliser that works on all lenses (gives about 2EV benefit but requires compatible OIS lens for greatest benefit) vs NO sensor based IS on the 6D – or any Canon dSLR for that matter!
• 117 PDAF autofocus points compared to 11 on the 6D which are all crowded in the centre
• face detection AF even when used with Canon lenses – vs face detection only in Live View mode
• eye detect AF with compatible lenses (not currently with the Canon lenses unless they are made by Sigma)
• 1200 zone metering instead of 63 zone dual layer metering
• flash sync 1/250th sec vs 1/180th sec – although my tests with Canon and Olympus flashes, the Sony a7ii only syncs fully at 1/200th sec – perhaps you need a Sony flash for 1/250th sec sync
• 1.23m dot tilting LCD vs 1mdot fixed LCD (unfortunately, neither offer touch screen)
• 1080HD 60p video vs 1080HD 30p
• more accurate AF and much less need for AF microadjustment as the PDAF sensors are on the main sensor not located elsewhere and hence need calibration

Benefits of the Canon 6D over the Sony a7II:

• similar interface to other Canon dSLRs, albeit a little crippled compared to its more expensive models
• optical viewfinder for those who value such things
• better batter life as no EVF
• more reliable AF with Canon lenses but you are restricted to those 11 points in the centre, and you don’t get face detect AF through the viewfinder let alone eye detection AF
• ability to use Canon flashes in TTL mode although the Cactus radio wireless TTL flash system is being updated in 2017 to allow Canon and Olympus flashes to work on Sony cameras with full TTL remote radio wireless flash – but apparently they can’t get HSS mode working at this stage!
  

Conclusion:

In the end, you need to work out which is best for you and the style of photography you do – both solutions are a long way from being ideal – they are both budget compromises – which compromise works for you – only you can tell!

For me, having an image stabilised Canon 135mm f/2L lens with face detect AF and ability to do Live View manual focus magnification with focus peaking in the viewfinder while using Canon Tilt-Shift lenses on the Sony with a better dynamic range and 1/8000th sec shutter for sunny days makes this a compelling choice for me if I were to purchase one of the two.