![]() A pixel is just numbers representing a color of a tiny dot location. Digital will make sense when you do think of pixels.įWIW, a digital pixel in an image file does NOT have a size, at least not until it is displayed, and is variable size in different print sizes. Ignoring pixels will never grasp the digital concept. Pixels are all there is in a digital image, and we must think of it that way. But enlarge these enough, and all you will see is the pixels or the individual tiles. Our brain recognizes the reproduced image pattern in those pixels or tiles. And then the pixel that describes a pink color is shown that color, which has the similar effect as a small piece of tile the same shade of pink. Tile and film both capture tiny samples of the actual color, but digital represents the colors with numbers, necessary because numbers can be written into the image file text, but actual colors cannot. The numeric concept may be relatively new today (called digital), but the concept of producing a picture in decorative tile is a few thousand years old. The color of each of millions of tiny dots is so described (a 6000 x 4000 pixel image is a grid of 24 million pixel locations).Ī pixel represents the color of a tiny dot with numbers, but conceptually is not unlike a small piece of colored tile in a mosaic tile picture (awesome). Then each pixel is ONE COLOR described digitally in numbers, representing the color of one tiny dot at its location in the image. The color in that tiny pixel's area was sampled by the camera or scanner sensor. ![]() A pixel is numeric data describing ONE RGB COLOR of one tiny area. The main concept of digital images is that each pixel is just NUMBERS. A pixel is purely numeric data representing some one color, of one tiny dot at its specific location in the image. Pixels are the most basic detail to know about digital imagesĪ digital image is composed entirely of pixels. But don't expect enlarging a printed image or a video screen image to go any further. Enlarging the original film or a straight-out-of-the-camera digital image might show more detail than otherwise seen, but when a digital image reaches the pixel size limit, all it shows is the pixels (as above). But that enlargement is just movie fiction, not at all real life. Specifically, this means 1200x1800 pixels printed at 300 dpi is 4圆 inches on paper.įWIW, some crime movies have shown how greatly enlarging a newspaper picture can reveal new details with clues about who dunnit. The rule of thumb for printing high quality photos is to have 300 pixels for every inch of print dimension (more or less, the 300 dpi need not be precisely exact, but for prints that will be viewed closely or hand-held, best quality is to stay within about 240 to 360 dpi, or 300 dpi). The trick is to have enough pixels for your enlargement size. □ Do realize the original 2502x3127 pixel (7.8 megapixels) image would look great printed 8.3×10.4 inches at 300 dpi, but this 12x size would print 8.3×10.4 feet at 25 dpi. This enlargement might look fuzzy, but actually each pixel is sharp. This example is to show the idea about pixels. The pixels do indicate the "fineness" of the smallest possible digital detail which is a pixel, and a pixel is just a dot of one color). We tend to think of these numbers as the "resolution" of the image, but at full size, it is the digital reproduction resolution of the image from the lens (the lens resolution is the limit). Then cropped to 2502x3127 pixels (4:5, 7.8 megapixels), and then resampled to 400x500 pixels (0.2 megapixels). This was a 4288x2828 (3:2) 12-megapixel Nikon D800 image but in portrait orientation. And there are different methods of compressing the data in the file, JPEG for one example. It is actually rather easy to grasp, if you get started right.Ĭolor images are commonly RGB data (three values per pixel representing Red, Green, Blue), but there are also other ways of encoding the image data, CYMK, grayscale, line art, indexed color (see more detail about bits). The concepts below are instead what you need to know to use digital images properly. This may perhaps be written a little like an argument, refuting the dumb incorrect myths we may have heard about how digital works. To be able to use digital images well, we need this understanding. The answer to virtually any question about image size starts with one of these basics. This page tries to be a quick summary of the digital concepts, about how things work. We just gotta know about pixels, and if any mystery, a very short primer is here: What is a Digital Image Anyway? But the detail is below Seriously, once we accept that pixels actually exist, then all this stuff is rather easy.
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