[JohnR]

Olympus and Panasonic announced a "micro" version of the 4/3 lens mount standard -

http://www.dpreview.com/news/0808/08080501microfourthirds.asp

In effect, this says that soon (?) there will be cameras on the market with the 4/3 size sensor but in a smaller body size than can be accomplished with an SLR. And, interchangeable lenses to boot. Is the new age of the "digital rangefinder" (in every sense except having an actual rangefinder) about to arrive?

Fingers crossed for reasonable prices on the new breed of camera.

[drphoto]

I've never heard of the term 4-thirds. But I've never been much of an equipment junkie. I'm guessing it describes a less than full frame sensor? But why 4-3rds? Why not 3/4 or 2/3 (or whatever) assuming full frame is 'one'?

[JohnR]

It's based on the same funky standard that you see for specifying sensor sizes in compacts, like 1/1.8" and so on. Wikipedia says

The name of the system comes from the size type of the image sensor used in the cameras. The image sensor is commonly referred to as a 4/3" type or 4/3 type sensor. The common inch-based sizing system is derived from vacuum image-sensing video camera tubes, which are now obsolete. The imaging area of a Four-Thirds sensor is equal to that of a video camera tube of 4/3" diameter.

Olympus and Panasonic SLRs use it.

[Goosepond]

In fact, one of the promises of the "new" 4/3 format back when it was introduced was that there would be much smaller cameras and lenses (read less expensive) than those big old full sized Canons and Nikons. This didn't pan out very well.

So this new announcement promises, by getting rid of the mirror box and optical VF, cameras will be significantly thinner and the lenses (read the old 4/3 lenses won't work, got to buy the new ones) will be smaller. And from what I read today on DPReview, they're not talking about rangefinders, just live view rear LCD's and EVF's.

Sounds like a communist plot to take all our money. 

I'll stick to my Canon 1Ds2 16mp behemoth that makes my biceps bigger every time I lift it. 

Gene

[JohnR]

Hm, well, to be fair, the Oly 4x0 series is still the smallest DSLR, esp when compared with kit lenses on. And at the time 4/3 was announced the smallest SLRs from Nikon at least were a fair bit bigger than they are now.

Current 4/3 lenses will mount on micro 4/3 with an adaptor.

I didn't literally mean a rangefinder (hence the quotes ) but was referring more to the size and character of the camera. Something like a digital version of my Bessa L - that would be cool Also note that, while the flange-sensor distance is halved, there is also (I am assuming, don't know for sure) that there is nothing to stop the lens from intruding into the camera in the same way that rangefinder lenses do. So the lenses can be even more compact because of that - maybe wide angles won't even need a retrofocus design?! Who knows