Why PHOTO(not video) camera companies(like Canon or Nikon or...) dont use 3 ccd technology surrounded by their products ?
Answers:
If you look at video cameras, you'll see that:
1) the pro ones are really big and
2) the 3-CCD ones that are not pro-level hold very tiny sensors.
By comparison, digital SLRs hold much larger sensors, and to be able to use a 3-CCD sensor similar to in a camcorder, the cameras would enjoy to be much larger and much more unwieldy.
Instead, most cameras use a single layer "Bayer Array" to receive accurate color. However, Foveon manufactures a 3-layer sensor for Sigma which is the functional equivalent of a 3-CCD sensor. The problem is that the Foveon, while deliver good color, is singular used in a mediocre Sigma camera, and the sensor doesn't own the same resolutions as other cameras (roughly 1/3 the resolution of most dignified megapixel SLRs). These factors hold kept the Sigma/Foveon from reaching bigger commercial success and taking on.
Note also that Fujifilm and Nikon have patent on similar technologies, so this is probably the surf of the future, as a channel of getting around sensor limits on megapixels.
In any satchel, in a few years, you will almost definitely see some kind of technology approaching a 3-CCD sensor (but modified into layers) used in digital cameras. If you think more or less it, how would you mount three different (APS-C or full frame) sensors and the beam splitter to distribute the RGB light to them contained by the space used now by one sensor .
If you check, you will see that 3 ccd video cameras are using much smaller sensors beside smaller pixel counts (like 3.1MP).
At this time, there really is no benefit of doing this beside DSLR cameras ... the Foveon X3 technology has on the other hand to prove effective, cost or trait wise.
Look at the one camera that does use that sensor.
http://www.dpreview.com/news/0609/060926...
If Sigma have one of these bodies that would accept Nikon or Canon lenses, perchance the pros would spend the $1,500 for the body and try it out, but as pros, we already have powerfully established techniques and to revise new metering practices and menu navigation, would slow us down.
That said, we won't really know until any Nikon or Canon comes up with a licensed Foveon X3 sensor contained by their cameras ... or something of a totally new design using discreet RGB sensors.