In October 2013, Sony introduced the a7 and a7R, the world's first full-frame mirrorless cameras with autofocus and electronic viewfinders. This marked a significant shift in the professional photography market, traditionally dominated by Canon and Nikon's larger DSLR cameras. The compact size and advanced features of Sony's new offerings challenged established norms, leading to a profound transformation in the industry over the following years.
Key Takeaways
- Sony launched the a7 and a7R in 2013, introducing the first full-frame autofocus mirrorless cameras.
- Canon and Nikon initially dismissed mirrorless technology as suitable only for consumers.
- Sony's strategic acquisitions and sensor technology gave it a competitive edge.
- The short flange distance of Sony's E-mount allowed for extensive lens adaptability.
- Five years passed before Canon and Nikon released competitive full-frame mirrorless systems.
The DSLR Era: Canon and Nikon's Dominance
Before 2013, Canon and Nikon held a near-monopoly in professional photography. Their DSLRs, like the Canon 5D Mark III and Nikon D800, were the standard. These cameras were large, heavy, and recognized by their distinctive mirror slap sound. Professionals relied on their extensive lens catalogs, robust support systems, and the perceived credibility associated with these brands.
Together, Canon and Nikon controlled approximately 75% of the interchangeable-lens camera market. This dominance extended even further among working professionals. Their ecosystems included not just camera bodies and lenses, but also flashes, accessories, and service centers. The industry had largely settled around these two major players.
Market Snapshot 2013
- 75%: Combined market share of Canon and Nikon in interchangeable-lens cameras.
- 5D Mark III & D800: Flagship DSLR models from Canon and Nikon, respectively.
- Optical Viewfinders: Standard in professional cameras before mirrorless innovation.
Both companies had explored mirrorless technology, but with smaller sensors. Canon introduced the EOS M in 2012 with an APS-C sensor, while Nikon launched the Nikon 1 series with an even smaller 1-inch sensor. This signaled their belief that mirrorless was for casual users, not for serious photographers who required larger, more robust equipment.
Sony's Calculated Entry into Full-Frame Mirrorless
Sony's entry into the full-frame mirrorless market was not a sudden move. It was the result of years of strategic planning. In 2006, Sony acquired Konica Minolta's camera division, gaining valuable optical expertise and the foundation for their A-mount system. This acquisition was a crucial step in building their imaging capabilities.
By 2010, Sony was experimenting with Single-Lens Translucent (SLT) cameras, such as the a77 and later the full-frame a99 in 2012. These cameras used a fixed, translucent mirror, enabling full-time phase-detect autofocus during video recording and utilizing high-resolution electronic viewfinders (EVFs). Sony was actively developing and refining the EVF experience, anticipating a shift in camera technology.
"Sony wasn't just a camera maker. They were (and still are) the world's leading image sensor supplier."
Sony's Preparatory Steps
- 2006: Acquired Konica Minolta's camera division.
- 2010: Launched APS-C mirrorless NEX system with E-mount.
- 2012: Introduced full-frame SLT a99, refining EVF and autofocus technology.
- Vertical Integration: Sony's role as a leading sensor supplier provided a significant R&D advantage.
Simultaneously, Sony launched their APS-C mirrorless NEX system in 2010, which used the E-mount. This mount would later become the standard for their full-frame mirrorless cameras. For three years, Sony used the NEX system to test the market, refine user experience, and expand its mirrorless ecosystem. The a7 was a fusion of their full-frame sensor technology and their proven E-mount mirrorless system.
The a7 Revolution: A New Standard Emerges
When Sony unveiled the a7 and a7R in October 2013, the specifications were groundbreaking. The a7 featured a full-frame sensor, comparable in size to those in the Canon 5D Mark III or Nikon D800, but in a body weighing only 474 grams without a lens. This was less than half the weight of Canon's flagship DSLR at the time. Its compact design allowed it to fit easily into a jacket pocket.
The key innovation was Sony's E-mount, with its remarkably short 18mm flange distance. In contrast, Canon's EF mount had a 44mm flange distance, and Nikon's F mount was 46.5mm. This technical detail, while seemingly minor, was critical. The mirrorless design eliminated the need for a bulky mirror box, allowing lenses to be mounted much closer to the sensor.
Lens Adaptability and New Possibilities
The short flange distance created a significant advantage: while long-flange lenses cannot be mounted on short-flange cameras, short-flange lenses can be mounted on long-flange cameras using a simple adapter. This meant photographers could use their existing Canon L-series or Nikon glass on a Sony body with adapters like Metabones. Even vintage Leica lenses became compatible, opening up a vast array of optical options.
Sony effectively bypassed the need to build a decades-long lens catalog from scratch. They allowed photographers to leverage their existing investments in other brands' glass. This adaptability was a powerful incentive for professionals to consider switching to Sony, challenging the notion of unbreakable lens ecosystems.
Key Innovations of the a7 Series
- Full-Frame Sensor: Professional-grade image quality in a compact body.
- Electronic Viewfinder (EVF): Real-time exposure preview, eliminating the need to check the LCD.
- Short Flange Distance (18mm): Enabled broad compatibility with adapted lenses.
- Advanced Video Capabilities: Integrated Sony's expertise in broadcast and cinema imaging.
Beyond lens adaptability, the a7 offered a fundamentally different imaging experience. Its electronic viewfinder displayed the final exposure before the shot was taken, streamlining the workflow. Sony also integrated its extensive expertise in video and broadcast imaging, honed from years of producing professional video cameras, directly into the a7 line. This positioned the a7 not just as a camera, but as a sophisticated computational imaging device.
The Giants' Miscalculation and Lost Years
Canon and Nikon largely dismissed the a7 as a niche product. They believed professionals preferred larger, more durable cameras with long battery life and familiar ergonomics. They also assumed their vast lens ecosystems created insurmountable switching costs for photographers.
This dismissal rested on three core assumptions:
- Size as a Feature: They believed a professional camera needed to be substantial, equating weight and size with quality and credibility. They overlooked the desire among professionals for lighter, more portable gear.
- Unbreakable Lens Ecosystems: Both companies had spent decades building extensive lens catalogs, assuming photographers would not abandon tens of thousands of dollars in glass.
- Protecting Legacy Businesses: Canon, in particular, had a successful Cinema EOS line and deliberately limited video features in its DSLRs to avoid cannibalizing those high-margin sales. Sony had no such legacy to protect and could integrate its best video technology into the a7 freely.
During this period, Canon continued to develop its APS-C EOS M system, while planning a separate, incompatible full-frame RF mount for the future. Nikon focused on its 1-inch sensor Nikon 1 system. Both companies saw mirrorless as a consumer-grade technology, missing the professional full-frame market Sony was actively cultivating.
Sony's Five-Year Lead: 2013-2018
For five critical years, Sony had the full-frame mirrorless market almost entirely to itself. They used this time to iterate and refine their technology relentlessly. In 2014, the a7 II introduced 5-axis in-body image stabilization (IBIS), a feature that stabilized every lens, native or adapted. The a7R II in 2015 featured a 42-megapixel sensor and improved autofocus.
In 2017, the a7R III offered dual card slots, significantly improved battery life, faster autofocus, and better handling. While Sony's initial E-mount lenses faced some criticism, the launch of their G Master series in 2016, starting with the 85mm f/1.4 GM, closed the quality gap. Third-party manufacturers like Sigma, Tamron, and Zeiss also began developing high-quality E-mount lenses, further strengthening Sony's ecosystem.
Sony's Rapid Iteration
- 2014: a7 II (first full-frame with 5-axis IBIS).
- 2015: a7R II (42MP sensor, improved AF).
- 2016: Launched G Master lens series.
- 2017: a7R III (dual card slots, better battery, faster AF).
- 2018: a7 III (benchmark for performance and value).
Meanwhile, Canon and Nikon focused on perfecting their DSLRs. Nikon released the D850 in 2017, widely praised as a masterpiece of DSLR engineering. Its success likely reinforced Nikon's belief in the longevity of the DSLR format, even as Sony was making mirrors obsolete.
The Game-Changer: Sony a7 III
The turning point arrived in February 2018 with the release of the Sony a7 III. This camera was a revelation for working professionals. It featured 693 phase-detection autofocus points covering 93% of the frame, along with advanced Eye-AF technology. It offered 10 frames per second burst shooting with continuous autofocus tracking, dual SD card slots, and oversampled 4K video from the full sensor width.
Priced at just $2,000 body-only at launch, it significantly undercut competitors like the Canon 5D Mark IV. For hybrid shooters who needed both high-quality photos and video, the a7 III offered unmatched performance and value. It became a default choice for a new generation of photographers.
Canon and Nikon's Late Response
In September 2018, Canon and Nikon finally unveiled their full-frame mirrorless systems: the Canon EOS R and the Nikon Z6/Z7. While these cameras appeared competitive on paper, their features often lagged behind Sony's third-generation offerings.
The Canon EOS R launched with a single SD card slot, a significant drawback for professionals who require backup. Its 4K video had a severe 1.7x crop factor, limiting its utility for serious video work. Nikon's Z6 and Z7, while offering excellent sensors, also launched with single card slots and autofocus systems that felt a generation behind Sony's advanced Eye-AF.
Both companies also launched with minimal native lens lineups. The EOS R had only four native RF lenses, and the Z system had three. While adapters were offered for their legacy DSLR lenses, this was Sony's strategy from 2013. Canon and Nikon were five years behind in building their native mirrorless glass collections.
The Aftermath: A Three-Way Battle
Canon and Nikon quickly learned from their initial missteps. By 2020, Canon released the R5 and R6, addressing many of the EOS R's shortcomings and introducing features like 8K video and dual card slots. Nikon followed with the Z6 II and Z7 II, and later the Z8 and Z9, which are now considered world-class mirrorless bodies capable of competing with Sony's flagship a1.
Today, the mirrorless market is a fierce three-way competition. Recent market data indicates that Canon has caught up to, and in some regions, surpassed Sony in new full-frame mirrorless sales. However, Sony still retains a significant advantage: those five formative years from 2013 to 2018.
Current Market Landscape
- Intense Competition: Canon, Nikon, and Sony now offer comparable high-end mirrorless systems.
- Sony's Ecosystem Advantage: Still boasts one of the most comprehensive native lens lineups and strong third-party support.
- New Generation of Photographers: Many entered the professional market during Sony's lead, building their businesses on E-mount.
During that period, Sony built the most comprehensive full-frame mirrorless ecosystem, with an extensive native lens lineup and robust third-party support from companies like Sigma and Tamron. More importantly, Sony captured an entire generation of photographers who entered the professional market during those years and built their businesses around the E-mount system. Rental houses continue to report Sony mirrorless gear among their most rented cameras.
The Sony a7 story serves as a powerful lesson in market disruption and the risks of incumbent complacency. Canon and Nikon, despite their resources and legacy, misjudged a fundamental shift in the camera market. They viewed it as a move from mirrors to mirrorless, rather than a transition from optical instruments to computational photography and hybrid tools. While they have regained ground, they spent a decade fighting to recover momentum that Sony seized by being first to market with a truly revolutionary product.