Archived posting to the Leica Users Group, 1999/10/13
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]This statement is wrong: "There is no need to make the pixels smaller than 5 um or so (that's 250 lp/mm already)." Below the real figures. 5 microns equals 5/1000 mm and thus equals 200 lines/mm or 100lp/mm 250lp/mm equals 500 lines/mm equals 2/1000 mm. This statement is false too: "Digital means a symbolic representation, period." In fact "Digital" means using only the digits 0 and 1, these numbers producing the simplest scale (binary scale) that uses positional notation where the value of each digit is multiplied by a power of the base depending on its position. A symbolic representation refers to anything that can carry a meaning and acts as a proxy to that meaning. The current French philosophers are masters in the art of naive nonsensical discourse based on hardly or falsely understood modern science. Read the book by Socal and Bricmont. This one is non true: "The human eye uses the same pattern of receptors, and so the alleged drawback of the CCD with a mosaic "filter in fact closely matches the actual mechanism of human vision. The human eye uses cones and rods, and the less numerous cones are responsible for color vision. Here we have a tri-stimulus mechanism where the cones have three different photo-sensitive substances (one substance per cone type). These signals travel along nerve fibres and are joined with the rods with complex connections and interactions. The tri-stimulus mechanism has a very superficial resemblance to the CCD mechanism in the popular digital camera, but it is close to the mechanism of the 3-color ccd linear arrays or the beamsplitting of Tv cameras. Any CCD sensor signal can be recorded as an analogue signal, no need for a digital capture here. So digital and analogue can be mixed as it is in the eye. Erwin