You also can end up getting pink clipped highlights. The improved color resolution comes at the cost of higher image noise and poorer roll-off of clipped highlights (since no raw reconstruction of clipped color channels is possible).This is particularly evident when photographing grass, where conventional debayering produces an almost monochromatic green, while the alternative process better differentiates the green of leaves from the reddish brown of trunks. The “Foveon-like” images tend to have better color differentiation and contrast, especially when the subject contains small, neighboring objects with different colors or shades of color.However, the edges can be jaggier and have false color fringes (especially when they were shot with cameras that have no antialiasing filter in front of the sensor). The “Foveon-like” images generally have sharper edges and details (for example, in hair).It’s similar to shooting two completely different film stocks with an analog still camera, such as negative film (traditional debayering) and slide film (our DIY Foveon-like RGB downsampling process).Ĭomparing the same camera images that were (a) conventionally debayered and downscaled by 50% and (b) RGB downscaled in our DIY “Foveon-like” process, the following differences become clear: In most cases, we simply get other kinds of colors. It can be difficult to compare results because in the “Foveon-like” process we completely bypass the camera manufacturer’s color science (and color calibration). (Note that this process only works for Bayer sensor cameras, not Fujifilm X-Trans cameras whose red/green/blue sensor filter pattern is larger than 4×4 pixels). Instead, we now create our own completely DIY raw processing and color science. Of course, it not only bypasses conventional raw debayering, but also camera manufacturer’s color science. This alternative process can be done quite easily with the Open Source software programs RawTherapee and Gimp or Darktable. 6-12 megapixel images can still be very usable. Nowadays, where 24-48 megapixels cameras are the norm, this alternative method comes with fewer drawbacks. Maybe no one has seriously considered this alternative approach yet because photographers wouldn’t have sacrificed their megapixels in the past. The idea is strikingly simple: If we don’t treat the four monochrome red + green + green + blue pixels of a Bayer sensor as four individual pixels, but mix them down into a single pixel, then that pixel will have true color, not the reconstructed color of conventional debayering and its algorithmic guesswork. Since no algorithmic reconstruction is required for the recorded pixels, both their color reproduction and per-pixel sharpness are unique.īut we can achieve a working equivalent of true color pixel capture for conventional Bayer sensor cameras – if we are willing to sacrifice megapixels in the final image. Foveon and 3-chip cameras, on the other hand, record true colors per pixel because their sensors can see red, blue and green simultaneously. The colors we see in the final 24 megapixel image were algorithmically guessed from this monochrome pixel grid.
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