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Digital SLR systems that have stopped or are no longer developing.Cropped mirrorless systems that have stopped or are no longer developing.

Actually, this is why it is so difficult to achieve 'correct' color rendition on many CDCs. In general, the camera does not see a color image at all, the camera's processor deals only with abstract numbers responsible for a separate shade of red, blue or green, and the creation of a color image is it's just math tricks. On the matrix there is only a set of sub-pixels (photo elements) of the Bayer pattern, from which, using special complex algorithms, 'real' image pixels are created. In fact, cameras using Bayer filter matrices (CCD, CMOS - it doesn't matter) have no declared real number of 'true' pixels. By the way, another appeared on Radozhiv interesting article и another one. In fact, there’s no difference CCD or CMOS - they still use the Bayer filter and subpexili for imaging.īut Sigma cameras with Foveon matrices have a much larger RAW file size for the same 12 MP compared to the CMOS matrix, which encode one real pixel using three pixels of the primary colors (as expected), this only confirms my reasoning. Important: similar calculations can be made for cameras using CCD sensors and uncompressed RAW files - Nikon D1, D1h, D1x, D100, D200as well as JFET (LBCAST) matrices - Nikon D2h, D2hs. It turns out that the RAW file also stores: But if we add data from the received 21,48 MB EXIF and JPEG PreviewImage then you can get the initial 24,4 MB. Given that there are 12 such sub-pixels on the matrix (the approximate number is indicated in the instructions), then the storage of information obtained from them will require:Īnd yet I never got the 24,4 MB that I see on my computer. In fact, the NEF file stores only 14-bit information for each sub-pixel of the Bayer filter, which is actually the same hue depth. Let us return to the calculations of the volume of files. Everything is tied to what exactly needs to be understood by the word 'pixel'. To put it very roughly, marketers have called the sub-pixels of the Bayer filter 'pixels' and thus made a substitution of the meaning of words.

12 million sub-pixels are sold to us for 12 million 'real pixels'. The main idea of ​​the article: sub-pixels and pixels. In the description for the camera you can see this: Question: why is it estimated that about 60 MB of memory is needed for one image, but in reality I only receive files at 24.4 MB? The secret lies in the fact that the original RAW file does not store the 'real' pixels, but information about the subpixels of the CMOS matrix Nikon D700. This equals 42 bytes, or 12 MB of memory. If encode images from my Nikon D700, without the use of data compression and compression algorithms, and with a 14-bit color depth, it turns out that you need to use 506 bits of information (we multiply 225 bits / pixel by 664 pixels). My Nikon D700 creates images of the maximum quality of 4256 by 2832 pixels, which gives exactly 12 pixels (about 052 million pixels, or simply 992 megapixels). And to encode one 'pixel' of the image in this way, you need 42 bits of memory:ġ4 bits R + 14 bits G + 14 bits B = 42 bits In fact, 4 billion is much more than necessary, for normal color reproduction, such a large supply of colors is used for easy image editing. (any of the four billion three hundred ninety eight billion forty six million five hundred eleven thousand one hundred and four colors). Thus, if we use 14-bit color depth, we can get any of 4 398 046 511 104 colors. The color is formed by mixing three basic shades - red R (Red), blue B (Blue), green G (Green). In this case, the files have a larger size and more accurate reproduction of shades' 'NEF (RAW) images are recorded at 14-bit color depth (16384 levels). For example, when you click on the 'question mark' button on the corresponding camera menu item Nikon D700 You can read the following: These pictures are most likely encoded using JPEG, and the JPEG algorithm is very flexible and for each individual thumbnail requires a different amount of information for storage.ġ4-bit color depth means that each of the three main shades encoded with 14 bits of memory. When viewing quickly, the camera does not require downloading a heavy 25 MB file, but simply pulls out a thumbnail preview image and displays it on its display. The preview image is used to quickly view the image on the camera monitor. I would like to draw your attention to the fact that the different weight of RAW (NEF) files is due to the fact that they carry not only useful 'raw' information, but also a small preview picture, as well as EXIF data module. Bytes to megabytes are translated very simply: Take, for example, the ARK-4820.NEF file, its weight is 25 bytes, or 621 MB. As you can see, the files are almost the same size.