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In the 2000's two digital cinema cameras, namely the Panavision Genesis and Sony F35, were launched with a pretty different sensor design called the RGB striped Array sensor (only these two cameras ever had this sensor design).

It is explained here:

The F35 RGB-striped sensor design is quite ingenious. It is arranged 2160 photosites vertically and 5760 photosites horizontally–or twice the vertical resolution and three times the horizontal resolution of a normal 1920×1080 HD raster. The photosite columns alternate colors: one column sees only red, the next sees only green, and the last sees only blue, and that sequence repeats horizontally across the surface of the chip.

Each pixel is created out of six photosites: two rows of red, green and blue are sampled vertically, and then those values are shifted horizontally to fall on top of each other. Imagine that these are the first two rows and three columns of photosites on the sensor:

R G B

R G B

First the two rows are added together vertically:

RR GG BB

Then the results are shifted on top of each other, so that R and G move right to stack on top of B. That becomes one pixel with a red, green and blue value derived from roughly the same spot on the chip:

RGB

Adding the signals from the two vertical photosites reduces noise significantly by doubling the color’s signal strength. Noise is random, which means that two random noise values added together never equals double the noise, so the color values are given a boost above the noise to create a very clean signal.

https://www.provideocoalition.com/non_technical_f35_guide/

Basically, this avoids the demosaicing process as with Bayer CFA sensors, but I'm wondering if there was possibly a deficiency in the design which is why it never caught on? Or just the fact that you needed 6x your required resolution in photosites made it undesirable? Too bad there is very little technical information on this sensor.

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  • \$\begingroup\$ A video camera is always used with the same orientation. A still camera; much less so. And you essentially have an anisotropic sensor... Also pixel binning is pretty common place now. And I suspect weird color artifacts along verticals with sharp contrast (in portait mode). \$\endgroup\$
    – xenoid
    Mar 27, 2023 at 19:43
  • \$\begingroup\$ "Basically, this avoids the demosaicing process as with Bayer CFA sensors..." is basically incorrect. There are several reasons, but the primary two are that: 1) The three colors of the filter arrays are not the same three colors as those emitted by our screens. We may call them "red", "green", and "blue," but the colors of the filters over our sensors are usually closer to Orange, Green, and Blue-Violet. 2) Color multipliers must be applied to account for the differences in the light illuminating the scene being photographed. \$\endgroup\$
    – Michael C
    Apr 8, 2023 at 8:18

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I think most of the benefit of this would come simply from the high resolution. That's over 12 megapixels, unheard of in the early 2000's.

The striped arrangement might have been simpler for calculating R,G,B values per pixel versus the Bayer arrangement. This certainly would have been a factor in the early 2000's. Today, not so much - the imaging pipelines are optimized for deBayer filtering and it occurs easily at video speeds.

The Moiré characteristics between the two would certainly be different, but without direct experience I couldn't tell you which would be better.

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It does not avoid the demosaicing process, it is just a different/proprietary demosaicing process compared to the more common Bayer array. Only a monochrome sensor avoids any demosaicing (and to a lesser extent a sensor like Foveon). Being proprietary in both design, implementation, and demosaicing, is a negative in itself.

As you noted, there is a significant loss of resolution due to the pixel binning. And unlike some other implementations of pixel binning it is "optional," which makes it a negative in that aspect.

There have been many different CFA designs over the years... but being different is generally a market negative; even if technically "better" in some aspect.

https://en.wikipedia.org/wiki/Color_filter_array

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  • \$\begingroup\$ Fuji doesn't suffer much from their use of their X-Trans CFA, so the market negative effect should not be overstated. \$\endgroup\$ Apr 2, 2023 at 16:46

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