Photography conference Photokina doesn't officially start until next week, but some camera makers have already made their high-profile announcements for the show. And judging by the announcements made by Sony and Nikon, there seems to be a emerging arms race in the prosumer camera market. The most exciting camera segment in the past few years has been the interchangeable mirrorless camera, raising the quality of compact and medium-sized cameras by incorporating larger sensors into smaller bodies. Samsung, Sony, and now even Canon have small mirrorless cameras with APS-C sized sensors, which traditionally were found in bulky DSLRs. But it seems like APS-C isn't enough.
For Photokina, Sony has announced the RX1, a compact camera around the size of its mirrorless NEX-7 but with a massive full-frame sensor. It's the smallest camera in the market with a full-frame sensor (smaller than the $7000 Leica M9), and though it doesn't support interchangeable lenses, sports a quality 35mm Carl Zeiss Sonnar f/2 lens. The 24MP sensor is about 2.4 times the size of an APS-C sensor, and photo quality is touted to be comparable to a Canon 5K Mark III or Nikon D800. Sony isn't positioning the RX1 as a replacement to DSLRs with interchangeable lenses, but a companion camera for professionals and prosumers who won't sacrifice image quality when they need to increase portability. The $2800 price tag puts it right under the cost of a D800, but we're talking about a camera that's less than a third of the weight of a fully-equipped DSLR. The RX1 also adopts features common to the higher end NEX cameras, like support for an OLED viewfinder and focus peaking on the high-resolution screen. The RX1 is shipping at the beginning of December.
Nikon is also bringing full-frame to "enthusiasts" with the D600, a $2100 DSLR that will be available next week. Here, Nikon has put a 24MP full-frame sensor into a mid-size body that's reminiscent of its prosumer D7000. Its features are understandably not as impressive as the popular D800, with ISO range of 100-6400 and 5.5fps continuous shooting. $2100 again can't really be considered affordable, though we do see a trend of putting full-frame sensors into camera not targeted strictly for professionals. (A used Canon 5D Mark II, for example, could be found online for around the same price.) Feedback for the D600 from commenters at DPreview are decidedly mixed.
Canon hasn't made its Photokina announcements yet, but the latest leaks also see it announcing a full-frame camera in a mid-sized body next week. The purported Canon 6D may have specs comparable to the D600 with a rumored price tag around $2000 as well. Again, not as affordable as the APS-C equipped 7D that many expected would be updated to full-frame, which signals that camera markers aren't ready to give up the profit margins they enjoy with those professional cameras.
As with the ongoing shift to APS-C in mirrorless cameras, just using a larger sensor doesn't automatically equate to the superior image quality. Sensor-size may correlate with better images (and low-light performance), but photographers need to consider many other factors as well. Dynamic range, noise and grain at high-ISO, and light fringing are just some of the metrics that should be examined when comparing cameras. In some ways, the new sensor size arms race is reminiscent of the megapixel race in point-and-shoots and its fallacies. Never rely on a singular spec to make your camera purchasing decisions.