Who would have thought that the victors would be the companies with open standard lens mounts?

No doubt about it. Canon and Nikon have spent decades making really good photographic products. And Kodak spent 100 years making better and better films. But in the case of the camera manufacturers it looks like the long term spoils will go to the camera companies that succeeded in creating the defacto open standards as they apply to lens mounts.

I've written for nearly five years now about the critical benefits of the EVFs with their instant and credible feedback loop for photography and we are now seeing that the tipping point has been reached and the trend makers in our industry are consistently reaching for the cameras that give them instant and effective live view on a full time basis. This delivers lots of benefits for most photographers with very few detractions.

Traditional mirrored DSLRs can be used in live view modes but those modes are still archaic, first gen. manifestations of real time live view that cripple the shooting and handling performance of the cameras. And, in every instance the operator must use the rear LCD screen to compose, focus and shoot with instead of being able to make use of a high resolution EVF. The traditional DSLR is quickly becoming synonymous with the idea of a hampered photographic experience because it can only be used in live view mode in a very basic and very unsatisfying way. One only has to try to shoot moving action with a DSLR in live view mode with his back to the sun in order to see, vividly, the limitations.

So the thing that mirror less cameras really brought to the table and the reason I use them in my work is not the smaller size and bulk of the systems but the fact that they have the most advanced and informative viewing system of all the tools available by dint of having a fully functional, real time feedback system. I'm found, over the years, that once you embrace the joy of "pre-chimping" a scene with a great feedback loop construct you'll never willingly go back to the optical finder with its inherent lack of information and immediacy.

For me, the size difference of the competing systems is a remotely secondary parameter in choosing between the different cameras.

But that's the draw for me and for generations of photographers who grew up dependent and happy with eye level viewing methods. That doesn't really speak to the reasons that many more people are embracing the mirror-less, compact cameras that are advancing in the market (with the exception of north America). No, I think an enormous number of ardent amateurs, semi-pros and wild artists are drawn toward the mirror less options because the shorter film plane to lens flange distance allow for easy adaptation of millions and millions of existing DSLR lenses that can work remarkably well on these cameras. In many (most?) instances you'll lose some niceties like auto focus and advanced program modes but you'll gain an almost infinite range of optical options, many of which have been available at bargain prices. It's the first really open standard lens mounting opportunity of the digital age!

I imagine that buyers of the Sony A7 variants will buy them as much for their ability to (with adapters) accept the best lenses from every competing system. With the purchase of just two adapters you'll have the run of the entire Canon and Nikon lens catalogs. Think the Nikon 105 DC lens is the best portrait lens ever made for full frame 35mm cameras? You are only one adapter away from using it on an A7. But do you also need a nice, 17mm tilt and shift lens? Of course you can adapt Canon's one of a kind 17mm T/S lens with ease.  Have you held onto a bag full of Leica R or M lenses? With the right adapter you'll be able to re-integrate (what many believe to be) the world's greatest glass with the addition of an inexpensive adapter.

The same applies to the micro four thirds cameras. Just about every optic made for photography in the past 50 years can be pretty well adapted to the Olympus or Panasonic cameras. In many cases the adapter rings can be as cheap as $25.

Having two systems that represent open lens standards effectively eliminates the one barrier to system entry that makes people so loathe to change to better cameras as technology evolves. The closed standards of traditional DSLR lens mounts held people with big investments in "glass" into systems that may have been leapfrogged by competitors who created better camera bodies.

I remember in the middle of the first decade of professional digital photography that many of use were locked into Nikon because that was a system we'd shot for years and years. In one sense we wanted to be locked in because the lenses were, in many cases, demonstrably better than competitive lenses in the same ranges. But we were stuck with the D2H and then the D2X APS-C cameras as our only real choices for camera bodies. The D2X at 12 megapixels was Nikon's highest resolution camera and everyone who ever owned one would tell you that you really couldn't shoot the machine effectively above 400 ISO because the noise quickly became unmanageable.

At the same time Canon was launching full frame cameras with more and more resolution and the ability to shoot at much higher ISO's without the unwanted Jackson Pollack Effect. Many of us would have loved to have incorporated a Canon body into our systems and to have been able to use one effectively with the lenses we knew, loved and had depreciated.

And then Nikon flipped the tables and came out with their D3, D3s and D3X cameras and I can only imagine that the Canon shooters would have loved to slap some of their better glass onto the Nikon, full frame cameras----mostly to take advantage of a wildly successful generation of fast, high ISO shooting tools but also, in the case of the sports photographers, to take advantage of a much more reliable focusing sports camera. And in fact many did switch over time from both sides of the aisles.

The introduction of the Sony Nex 7 offered a delicious taste of freedom for Leica M users who could, for the first time, get great files from their investment in M lenses, albeit with a cropped frame. The Sony A7's will mean that the M users (and the few R users) will get to use their lens investments on a full frame camera with equally good imaging performance but at a quarter the price of the Leica M body.

If you are not operating in the lofty heights of Leica lenses the micro four thirds offers so many choices that it must be embarrassing for their more traditional rivals. And the idea that I can buy a Panasonic GH3 because I want the great video performance and then I can buy a OMD EM-1 for the image stabilization and possible improvement in jpeg images SOOC but still keep to one line of lenses is equally seductive. For my Panasonic system I can opt to cherry pick each companies line of lenses. Say the Panasonic 7 to 14mm for the shorter focal lengths, the Olympus 17mm 1.8 for a quick PJ lens, the wildly good Pana/Leica 25mm lens for everyday wear, the high performance Olympus 45mm 1.8 for discreet portrait work, the 35-100 f2.8 from Panansonic for stage work and so on.

If Olympus comes out with a better video body then....adios Panasonic but without the usual disruption and financial loss of having to re-rationalize the lens collection. It all seems so logical.
Wide open standards so you can optimize your systems for the way you shoot. That trumps the arguments about size and price and puts the focus on the stuff that focuses....

Nikonians love Nikons and Apple Computer users love their Macs. But the reality is that the market rewards companies that offer products which feature open standards. And that means millions of people are trying Android systems or buying Linux machines, using Java and opting for open standards even within Microsoft OS environments.  And for good reason....the consumer gets to choose the best "apps" for their use. And they get to hang on to their investments as they upgrade their platforms.

It's not about mirror less cameras, per se. It's more about open standards in the most expensive aspect of the hobby/vocation, the collection of good lenses. Just as it's not about camera size as much as it is about the convenience of use that comes from EVFs and more mature and useful visual feedback loops. Feedback loops that don't require iterative test shots.

It's only a matter of time before Canon and Nikon follow Sony, Olympus, Fuji and Panasonic into mirror less cameras. They will make short film flange to sensor plane cameras if for no other reason than to compete in the open systems market. It's all about the most efficient ecosystems, even if that's harder for consumers to articulate in surveys. And it's all changing right now.