Feb 052011

This week Ricoh announced it was developing an M-mount module for its GXR cameras. As much as I love Ricoh cameras, this module and the GXR will not be at the top of my shopping list.

I do not own any Leica M-mount lenses; if I did, I would be shooting with a Leica M9 camera, which blows the GXR, fine camera that it is, out of the water.

I am also somewhat troubled by this announcement because it seems to fly in the face of what Ricoh was saying when it first launched the GXR system — a system where the lens and sensor are combined into a module that some call a lensor.

Introducing this new concept in digital cameras, Ricoh stated:

It is the lens that gives life to the photograph. In interchangeable lens camera systems up to now, the distance from the mount and the back of the lens to the sensor image plane was subject to requirements for flange back distance and back focal length. This made it difficult to achieve both compactness and high optical performance. Eliminating the lens mount, however, means that the back focal length can be freely defined for the GXR, enabling the new system to use the most optically efficient lens designs and giving it excellent potential for future expansion. This practical concept has given birth to camera units that achieve compact size without compromising image quality.

In order to make the best use of the inherent power of the lens and the image sensor, the ideal solution is to combine both in a single unit. Consider, for example, the low-pass filter covering the surface of the image sensor. The dilemma faced is that while the filter helps prevent color noise and color moiré, increasing this benefit results in an ever greater sacrifice in lens resolution. Traditional interchangeable lens systems use a single low-pass filter for all lenses so they are unable to avoid situations where the filter effect is excessive or inadequate. With the GXR, on the other hand, we can design a filter optimized for the resolution of the specific lens. In this way, Ricoh has succeeded in effectively preventing color noise while suppressing filter influence on lens resolution.

The ease with which dust can adhere to image sensors has been a system problem for interchangeable lens digital cameras up to now. In the case of GXR camera units, however, the lens and the image sensor are integrated into a single unit. This structure makes it difficult for dust to get in since it is not necessary to expose the inside of the camera when changing lenses. In addition, the inside of the units are highly airtight with light-shielded walls. Even in highly dusty shooting environments, camera units can be changed without hesitation.

The planned introduction of an interchangeable lens mount in autumn suggests to me that all the above was advertizing hype. Having made the case for not introducing a camera that allows interchangeable lenses, Ricoh appear to have done a U-turn.

The M-mount module has been well received by most people on the Ricoh Forum of DPReview, although a few people do express concerns similar to mine.

In theory it sounds fine to be able to fit one of the the best lenses in the world, Leica lenses undoubtedly are as their cost reflects, but focusing them is not going to be an easy task. The electronic viewfinder that can be bought as an accessory for the GXR will become an essential item for anyone wishing to use manual focus lenses. Trying to focus a heavy lens at arm’s length using the LCD will not be easy, unless your arms have muscles of steel.

No doubt those people who persevere with the GXR and an attached Leica lens will produce good results but not with every shot they take. They will have to get used bracket focusing, for want of a better term, whereby you get the subject in focus and then keep tweaking the focus a fraction on successive shots. Viewing all the shots on a computer screen will reveal the one truly in focus. That approach is fine for static subjects, not so good for anything that moves. And those that think focus confirmation is the answer are in for a rude awakening. Focus confirmation can assist but it will not nail the sharpest focus.

When I bought my GRD III, I was torn between waiting six months or so for the launch of the GXR with a 28mm lens module. The great advantage the GRD III has over the GXR is its compactness, which means the GRD is always with me. There is no denying that the APS-C sensor of the GXR is far superior to the CCD sensor in the GRD III but that superiority only becomes really marked at higher ISO settings. But what good would that superior image quality be if the camera is sitting on the desk in my office.

As the saying goes, the best camera is the one that you have with you and for me that is the Ricoh GRD III.

I would have much preferred Ricoh to have expanded its range of lens modules for the GXR and so make it a more complete, as well as innovative system, to compete with the micro four-thirds cameras.