Olympus Brings Down The Curtain On The Legacy Four Thirds System

Olympus brings down the curtain on the legacy Four Thirds systemIt probably shouldn't be a surprise but it's still a little sad to see it in print: the latest catalogue from four-thirds.org states that production of Olympus's Zuiko Digital line of Four Thirds lenses has been discontinued.
It's been six and a half years since the launch of the last Four Thirds mount camera, so it's understandable that Olympus has decided to move on, but we thought we'd look back at Four Thirds: what it meant and where it led.

Where it all started

In 1999, Olympus engineer Katsuhiro Takada selected the 4/3"-type sensor as being the optimal size to allow smaller cameras capable of high quality images. Olympus developed the lens mount and communication protocols and was joined by other makers including Kodak, Fujifilm and Panasonic. The Four Thirds system website was launched fourteen years ago tomorrow.

Four Thirds was the first ILC system specifically designed for digital. This not only meant a wholly new lens system, providing the focal lengths that make sense for the sensor size (at a time when most camera companies were making do with selling film lenses mounted on smaller sensors), but also adopting a policy of making telecentric designs, which project light straight onto the sensor, rather than at increasingly challenging angles, towards the edge of the sensor.

Unfortunately, the telecentric lens designs often ended up being relatively large, meaning that the system didn't end up being significantly smaller than APS-C cameras. Unfortunately, the decision to use 4/3"-type sensors also meant that the viewfinders in most of the models were even smaller than those that still plague most low-end APS-C DSLRs.

While the Four Thirds system is no longer with us, it's worth giving credit for the innovations it played host to. For a start, it was the first interchangeable lens system to offer live view. It wasn't the slickest of implementations: seemingly unsure whether live view was supposed to offer an immediate digital preview (with phase detection still available) or provide the precision of contrast detect AF and live view magnification, the E-330 offered both. And was duly given short shrift by DPReview founder Phil Askey in his review.

The system evolves

However, the most significant development to come out of Four Thirds, though, was its successor, Micro Four Thirds, the world's first mirrorless interchangeable lens camera system (indeed the system for which the term was coined). Micro Four Thirds persisted with the Four Thirds type sensor but by abandoning the mirror box (and the telecentric design philosophy) was able to fully deliver on the size benefits that had originally been promised.

Without a mirror to move out of the way, live view came into its own and a whole new class of camera was born.

Credit should be given to Olympus for working to provide cameras (specifically the E-M1s) that were designed to continue to give good performance for those users who'd bought the highest-end Four Thirds lenses.

Long live Four Thirds

The history of photography is full of defunct systems and obsolete mounts. Even though the curtain has come down on Four Thirds, you can still buy a camera that will make good use of its lenses. The king is dead...