The mirrorless camera was an innocuous enough invention that stemmed from Olympus' early innovation, but is it Sony that has managed to change the camera market for good and upset the CaNikon apple cart?
The Single Lens Reflex, or SLR, was the mechanical solution to the thorny problem of framing an image on a roll film camera. Unlike a view camera where you look at the ground screen before inserting and exposing the dark slide, in a roll film camera, you don't get to look through the lens. The simplest solution is to have a view window, however, this doesn't see what the lens sees and if you change lenses then the view changes.
A more sophisticated answer came in the form of the rangefinder which made parallax corrections for the offset viewfinder with different frame lines for different focal length lenses. An alternative was provided by the Twin Lens Reflex (TLR) which had a second lens sat above the primary exposure lens and offered a near-identical view. Unfortunately, neither of these solutions showed what the lens was seeing which is where the SLR came in. Through the relatively complex — and expensive — mirrorbox and pentaprism combination, a photographer could see what the camera saw, then flip the mirror out of the way and release the shutter to expose the film, before returning the mirror into position. It is mechanically elegant which is why it has stood the test of time.
You could probably argue that the advent of digital cameras heralded the demise of the SLR. Manufacturers realized from the earliest designs that with a digital sensor you could view in real-time what the camera was seeing. In short, you are taking a video feed and viewing it on screen. Of course, the technology to achieve this wasn't available in the earliest cameras, with no facility to even view images. On-screen image playback came before the addition of video recording and then "live view". The genesis of the camera was evolutionary, however, which meant encompassing digital workflows within existing designs and so was born the Nikon D1 which spawned the dominant camera design for the next twenty years.
It was not long after the arrival of the D1 that the seeds of the mirrorless revolution were born in the form of the Olympus E-1 and the Four Thirds system. Strictly a DSLR, the design premise was a compact system built around a small sensor with long reach. So while the Epson RD1 might take the plaudits as the first mirrorless camera, it was the launch of the Micro Four Thirds system in 2008 in the form of the Panasonic G1 that spawned a revolution.
Sony Takes Center Stage
While mirrorless might have had a slow burn from the E-1 to the G1, the years that followed immediately after were a melting pot of innovation. Manufacturers fell over themselves to release new systems: Sony in 2010 (NEX-3; APS-C), along with Nikon (Nikon 1 V1; CX) and Pentax (Q; 1/2.3") in 2011, Canon in 2012 (EOS M; APS-C), Fuji in 2012 (X-Pro1; APS-C), Pentax again in 2012 (K-01; APS-C), Sony again in 2013 (a7; FF). and Leica in 2014 (Leica T Typ701; FF). It's perhaps a little disingenuous to classify these systems by their sensor size as there was plenty of innovation going on in their designs, however, it is a good indicator of what their target market was. More importantly, their lens mounts were designed with sensor size in mind and it's arguable that Sony's E-mount was never intended to house a full frame sensor. As can be seen from this list, the APS-C specification was popular as it offered a balance between system size and image quality. System size, more than anything, was the driving force behind these cameras with Micro Four Thirds being particularly portable, along with the Nikon 1 and Pentax Q. In short, while everyone wanted to jump on the mirrorless bandwagon, nobody saw it as a replacement for the DSLR, at least not initially. It's not surprising then that some manufacturers saw increasing scope in mirrorless and Olympus' OM-D E-M5 and Fuji's X-Pro1 are notable for their move away from a primarily consumer-oriented focus.
It was Sony's decision to stick a full frame sensor inside the a7 that permanently changed the sector. So where did that leave everyone else? At this stage it was not a foregone conclusion that mirrorless was the next iteration of the camera, however, the Pentax Q and K01 were already dead in the water. The Nikon 1 built out a consumer system that was liked but it was only ever a niche product, so much so that it was killed off in 2018. Canon still has the EOS M, however, it must remain in a quandary as to what to do about it. Nikon's strategy of producing APS-C and FF versions of its Z-mount system gives it an edge while also reducing production costs. A quiet death seems a likely outcome for the EOS M and it would perhaps be better for Canon to do this sooner rather than later.
Fuji has managed to ply a healthy trade in cameras sales, although it is its analog Instax that is the star of the business show and it's questionable as to whether the digital sub-division makes a profit. Its APS-C/medium format strategy has won it many admirers and it sells well enough for it to continue with development. That leaves Olympus, Panasonic, and Leica. Olympus' sale of its Imaging Division has been met with concern, but new models are coming although sales appear to have dropped making 2021 a formative year under its new owners. The Leica T Typ701 is notable for introducing the L-mount which now ties Sigma and Panasonic in to the Alliance. Panasonic again sells a healthy number of Micro Four Thirds cameras with their video-focused features. Quite how well the FF offerings will do remains to be seen. Will they become a genuine FF alternative to Nikon and Canon?
How the Future Unfolded
As it turned out, Sony was in the right place at the right time with the right strategy when mirrorless was unleashed upon the world. It had recently purchased Minolta and this provided the capability and capacity to produce new, technically innovative, cameras. Minolta was firmly embedded in the DSLR tradition, so this was a genuine choice by Sony. That it took so long for anyone other than Leica to release a FF model is a surprise and Sony appeared to have an unassailable vice-like grip on the market after those 5 long years before Canon and Nikon responded. What's more remarkable is the speed with which Canon has pivoted its sales from DSLR to mirrorless and is now selling almost the same number of mirrorless cameras as Sony.
There are some salient points to take away from this: firstly, technical innovation can take you in unexpected directions. Sony wasn't heavily invested in DSLRs so experimenting with new formats, such as mirrorless and SLT, was easier to do. For Nikon and Canon, income from camera sales and future technical investment was predicated on the success of the DSLR making them less responsive to change. Secondly, Sony is a consumer electronics company and has a different design ethos to Nikon and Canon, and this is clearly demonstrated in the cameras they produce. Is the ability to appeal to photographers one of the reasons behinds Canon's success? Thirdly, consumers are less concerned with the history of the camera industry and manufacturers of all sizes come and go. The last decade has made us familiar with the Sony-Canon-Nikon triumvirate and it's unlikely this is going to change, however, expect there to be a bumpy ride in the fortunes of all manufacturers.
Finally, how long will mirrorless be the defining camera design? Sure, there will be innovations around this such as global shutters and the integration of elements of the smartphone, but will it fundamentally change any further, or are we at the culmination of design for the next century?