Otto PETER wrote: >There is an additional aspect: Each > individual sensor for each pixel has slightly different properties - no > way to make them really alike. This probably also causes some "grain", > but since the pattern is the same for each exposure, it might be > compensated automatically by subtracting the result of a dark exposure > with the same exposure time - as far as I know, cameras do that, at > least for long exposure times. >
that cannot compensate for pure amplifier noise which is random and therefore cannot be compensated for unless many identical images are taken in the same session and averaged the sensor is also not wholly predictable and produces random noise which may or may not be present in low as well as high exposure conditions you may not notice it in high exposure conditions as there is a lot of detail to fool the eye philip =============================================================== GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE
