It's a Photokina year, so it's not surprising that Panasonic would be announcing something besides its advanced compact, but the company has been firmly Four Thirds since its first interchangeable-lens model came out over 10 years ago. So the rumor that the company plans to show a prototype of a full-frame camera on Sept. 25 at the show, for release next year, comes as a surprise.
There's also a countdown page for its press conference, which means something big is probably in the works.
The news was broken by 43rumors, which gives it an "FT5" probability rating -- its highest level. And it comes after similarly high-probability rumors in July (which I missed) of a high-end Olympus model with a new sensor format. Since Olympus is also a Four Thirds company, it's pretty compelling evidence for a new-size sensor.
To recap, full-frame sensors are signficantly larger than the Four Thirds sensors in Panasonic and Olympus cameras, with a 3:2 aspect ratio compared to the smaller's 4:3. Note that the Four Thirds sensor size is distinct from the Micro Four Thirds mount (despite how I labeled the graphic below).
It's a notable development for a couple of reasons. The different sensor aspect ratios require different lens mounts for one. Micro Four Thirds, helmed by Olympus and Panasonic, is a licensable lens standard, compared to the proprietary mounts from Nikon, Canon and Sony. So it's possible that any full-frame mount might be open as well.
If true, it also means that we may finally get much better low-light and higher-resolution images from Panasonic. Micro Four Thirds models are great in tons of ways -- system size is one of the biggest -- but low-light quality has never matched that of full-frame or even APS-C models, mostly because of the smaller sensor size, which has also limited the maximum resolution -- it currently tops out at 20 or so megapixels.
However, it's not necessarily a full-frame sensor, which harkens back to the size of a frame of 35mm film. It could be a new, larger-size Four Thirds sensor that would encompass full-frame so you could use those lenses with an adapter using some kind of multiaspect mode.
Some people are speculating that since Leica is Panasonic's long-time lens partner that Panasonic might use the SL-Mount that Leica uses for its , though I kind of hope not, since those lenses are really big. What would likely make sense is hybrid mount that could also take MFT lenses for a crop mode.
Since its cameras are native mirrorless, they may not need an adapter the way you need to mount a DSLR lens on a mirrorless camera; the adapters adjust the distance between the sensor and the lens (the flange distance) to compensate for the absence of a mirror.
The full-frame mirrorless segment is currently owned by Sony's A series thanks to a several-year head start. But Nikon has just jumped in with itsand Canon's EOS R full-frame mirrorless announcement is rumored to be imminent. However, Panasonic has been innovating a lot in the mirrorless space and working it for a lot longer than either Nikon or Canon, so it would be very interesting to see what kind of developments it brings to the format.
Panasonic declined to comment.