FULL RGB Sensor Technology Advances - When will Video Catch Up?

[Jacob Mason]

With today's interesting report from DPReview on Nikon's patented and yet-to-be announced Full RGB Image Sensor, (Article Here) it appears that the concept Foveon X3 introduced is finally showing renewed signs of life in digital photography, but...what about video?

As some of you may remember, one of the major breakthroughs in sensor technology for digital cameras in recent years was the Foveon X3 sensor (Info. on Foveon X3 Sensor Here), used exclusively on Sigma DSLRs and some p&s cameras. While it showed promise upon its initial release, it has sort of stalled out, leaving more to be desired by Professionals and more to be provided by other companies who have the means to creatively captitalize on this innovation.

What made this type of sensor so unique was its ability to capture in FULL RGB, thus leaving it with some signficant advantages over traditional CCD and CMOS sensors.

The operation of the Foveon X3 sensor is quite different from that of the Bayer filter image sensor more commonly used in digital cameras. In the Bayer sensor, each photosite in the array consists of a single light sensor (either CMOS or CCD) that, as a result of filtration, is exposed to only one of the three primary colors, red, green, or blue. Constructing a full color image from a Bayer sensor requires demosaicing, an interpolative process in which the output pixel associated with each photosite is assigned an RGB value based on the level of red, green, and blue reported by those photosites adjacent to it. The Foveon X3 sensor creates its RGB color output for each photosite by combining the outputs of each of the stacked photodiodes at each of its photosites. This operational difference results in several significant consequences. More

Then, last year reports surfaced on Fuji Film's patented and yet-to-be official OCMOS Image Sensor, which seemed to have adopted a similar concept of vertical stacking, but through a special use of organic pigments which give direct responses to red, green, or blue light.
However, Fuji Film's OCMOS sensor still may not be implemented for another 3 years.
Although, one thing that was of particular interest to me with regard to the Fuji Film OCMOS patent was the wording which specifically covered applications not only designated for digital photography, but also for digital cinematography.

Here, hopefully very soon, we will have this technology available in video cameras.
When reviewing the list of companies that are responsible for these innovations, one tries to speculate on who will benefit first by connecting them with the companies that are already working with them. At this time, I can't really draw any definitive conclusions on whether Sony, Canon, or Panasonic would have it first. Maybe it won't be any of them.

[Glenn Chan]

When it comes to sensor design, there are multiple tradeoffs to be made. One design may be good at one thing and bad at others. The Foveon design is susceptible to noise / doesn't have that good dynamic range. In practice... the best results are still coming from dSLRs.

For video... the best results (though this depends on taste) are coming from 35mm film. Though the Bayer approach of Red might challenge that.
For VFX work, what Red has shown (old Redcode-compressed footage) shows that it is very good for greenscreen (where color resolution is one of many desirable traits).

So when it comes down to it, the most practical thing to do is to evaluate products that exist and see how they work in practice. Products or technologies that are good in theory don't always turn out that way.