4/3rds Format

[milest]

Well, all other manufacturers use the same mount as their film cameras. That 35mm image circle is called "full frame" in the digital world. Full frame sensors are still very expensive but will get cheaper. There are also medium format backs that use existing MF camera bodies and lenses. What this does is preserve your investment in lenses, much more expensive than camera bodies.

You may already know this but your OM lenses will not fit on the Olympus digital cameras. Unlike everyone else, Olympus changed the entire mount.

Heard that response of sensors to incident light was different to that of film, hence full frame sensor only provided optimal digital performance if lens mount 'optimised' for sensor which of course precluded preservation of previous investment (but the finer points of camera design are definitely beyond me and I doubt I couldtellany difference). Of course, that's Olympus's line and ultimately it comes down to personal preference. Re last line, the web says Olympus does make, and even sometimes give away, a converter ring. I shall sit back and ponder awhile; all my investment is 20 years old! Thanks for your input.

[Sebastian]

Micheal is right, and it is ultimately very simple.

A CCD/CMOS is an analog device, it reads light and converts it to current. The larger the pixel, the more light hits it, and the stronger the signal. Compare a full-frame 8 megapixel sensor to a 4/3 8 megapixel sensor and the 4/3 sensor will have to have it's "gain" turned up higher to squeeze the same sensitivity out of it at the same settings as the larger sensor. And since the "gain" is being turned up noise is introduced, color saturation suffers and dynamic range in decreased. In the end, a bigger pixel is ALWAYS better than a smaller pixel.

As for larger sensors having different reactions to incident light than film, you are referring to the angle of the light hitting the sensor. Film is a two-dimensional medium, whereas sensors are three-dimensional, the pixels have depth. Therefore towards the edges light tends to fall off, just like it does on film due to lens limitations, because the light is not hitting the plane at a right angle. This is largely remedied by different designs of pixels to redirect most of the light correctly and is really not that big of a problem, and is so slight that it can be easily fixed with software in the somewhat limited instances that it's required. Still, the ability to record better color and less noise on a larger sensor greatly outweighs this issue, since this is a minor problem at worst, and excessive noise and lack of dynamic range are much more serious.

So in the end, I would say one thing differently from the way Michael put it, the larger PIXEL will always win, all other things being equal.

Now, technology progresses, and the quality of smaller pixels today is much greater than what it used to be with much larger pixels. Sensors today are produced in ways that limit signal spill, processing units are positioned to minimize impact on sensors, pixels are read differently than they used to be, so TODAY's pixels, although much smaller than what they used to be, take much nicer pictures than pixels of just a few years ago. BUT, the technology applied to a smaller pixel TODAY still will lose out to a larger pixel made today. Once again echoing what Michael said, improvements apply to both types of sensor, and then the deciding factor will be the basic stuff outlined in the beginning of this post.

As for Olympus, the are not really innovating in that area. They don't have the R&D and ability to develop these quality-improving technologies. And their partner in this whole standard is Kodak, who has shown time and again that they have no business designing sensors, as the 14n's has been a train wreck. Olympus instead depends on other companies to innovate, at which point they can license the technology and incorporate it, or learn manufacturing tricks from others.

Canon and Nikon are the two top dogs, and the reason Canon took the lead in the digital realm was because they have an incredible division that produces their own sensors, and they bring the technology to market as soon as it's ready. Nikon's attempt at their own sensor design in the D2h was weak, and they continue to use Sony's work in their new flagship D2x. For them being a producer of the machines that make the processors and sensors was not enough to be able to actually make a good part themselves. Sony has much more experience in this regard, and that's why Sony cameras tend to consistently be near the top in image quality, and why the partnership with nikon continues into the foreseeable future.

Now to add one more piece of opinion to all of this, I think Olympus is way too underfunded and inexperienced to try to make any sort of digital standard, and Kodak simply has had a bad track record. I don't see a future in 4/3s, I think it was too short-sighted and too late to market. Progress doesn't wait for potentially good ideas, when they don't come or don't deliver it replaces them with something better. The problem that Olympus needs to overcome is that there already is something better, and it's getting better faster than what they can deliver. I just don't see any way their system is competitive with anything else on the market.