To best understand what the new GXR interchangeable lens camera from Ricoh is all about, take a look at the diagram above we grabbed from the press presentation.

The lens units are so much more than optics: they are a complete imaging unit. Packed in behind the glass you have the sensor, which will differ between lenses, as well as processors and motion sensors. The "camera" won't be limited by what you have in the main body, moreover, it will be defined by what you have in the lens unit.

The launch lenses are the GR Lens A12 50mm F2.5 Macro and the Ricoh Lens S10 24-72mm F2.5-4.4 VC (vibration compensation). The properties of these lenses are entirely different – it isn't just the focal length.

The GR lens has a 12.3-mexapixel 23.6 x 15.7mm CMOS sensor and it is capable of 720p HD movie capture: it costs £600 and will give you a 16:9 aspect image. The Ricoh lens has a 10-megapixel 1/1.7-inch CCD sensor and will only be good for VGA quality video: it's half the price of the GR lens, giving you a 4:3 aspect image.

The former is what you might expect from a DLSR camera, the latter, a compact camera. But what happens if you don't want to bump down to a lesser quality sensor just because you want a zoom lens?

The other side of the diagram shows what is packed into the body itself: another image processor, the battery, memory, flash, LCD and all the connectivity. Not only will you be able to buy different lens units, but in the future, potentially, you could be buying an entirely different body that fits with the system.

The two are connected by a single interface and as a sealed unit, you don't have to worry about dust and debris getting onto your imaging sensor, which Ricoh are pushing as a significant bonus of the system.

Check out the magnesium alloy body below and if you want to get heavy with pictures, head over to our hands-on photo gallery.