> Now that you've gotten (apparently very) close to what Phil's seen
> are you willing to tackle the looming and much debated question of
> the Foveon to Bayer equivalence?
>
> Some people say that 3MP is going to be about as useful as 4.5 to
> 5MP, others say 6, and some more aggressive people think 7! Then
> there's some crazies saying 9, 10, 11, and I've even seen 14 [wow,
> some people aren't "thinkers"].

The problem on the issue of "Foveon to Bayer equivalence" is that the two will *never* be "equivalent" no matter what figure you choose. That is the main reason that I started my page: to show that to compare the two technologies, you have to review different aspects of image quality.

I know that everyone wants a number that represents simply a *resolution* equivalence without considering overall quality. Even that cannot be done, because the resolution of a Bayer sensor is far from static; it is all over the place. A 3.4 MP Foveon sensor is probably going to resolve about as much detail as a 5 to 6 MP Bayer sensor for black/white detail with no chrominance component (although the Bayer version probably wouldn't be as sharp). The same 3.4 MP Foveon sensor will resolve as much detail as a 13.5 MP Bayer sensor for true reds and blues and combinations of those two colors. Other colors will lie somewhere in between.

How that affects the "perception" of resolution and how large images can be printed will therefore largely depend on image content and will be different from image to image. I expect this debate will rage on even *after* Phil posts his final review of the SD9 because for everyone who posts a 6 MP Bayer versus 3.4 MP X3 image that shows a slight advantage to the 6 MP Bayer, someone else will post another one that shows an X3 advantage.

Following some of my previous examples, if two photographers took a picture of the same bright red sports car, one using an SD9 and one using the new 14 MP Kodak, both would resolve about the same level of detail in areas where red meets black on the car: like the space between the door and the front fender, space between the hood and front bumper, where the black window seal meets the top of the door, etc. But... in that same picture, you may have green grass in the background with a white sign in the distance with black lettering. I would expect the Kodak to blow the SD9 away on those details while just barely matching the SD9 in the details of red/black in the car. So which is better? You'll get some people arguing that the Kodak is better because it resolves just as much detail in the car but much more in the background. Others will argue that the SD9 picture is better because the resolving power is more linear and doesn't make the background look sharper than the foreground (car).

As to overall image quality (not limiting ourselves to resolution), I predict that the SD9 will be more than a match for any 6 MP dSLR. In some areas of some pics, it will lose to a 6 MP Bayer. In others, it will excel. Overall, you have to look at image quality of a "random" image as being based on simple data collection. The simple fact of the matter is that a 3.4 MP X3 sensor such as that in the SD9 will capture 1.7 times as much information as a 6 MP Bayer dSLR, plus or minus some relatively small adjustment for the way the two technologies are designed and the fact that nothing is ever a "simple" comparison.

Since the SD9 captures over 10 million samples of information while a 6 MP Bayer camera only captures 6 million samples, the increased "data acquisition" of the SD9 is going to contribute to image quality in some way, but quantifying that advantage via visual comparisons is something that people will go on debating until the demise of the Bayer sensor.

So all I can say is Phil... I hope you have plenty of extra forum space on your server(s). :-)

--
Mike
http://www.ddisoftware.com