Dario Bonazza wrote: > I keep thinking in photographic terms. In my understanding, exposure depends > on: > > 1 - Subject's brightness > 2 - Lens aperture > 3 - Shutter speed > 4 - Film/Sensor sensitivity > > Sure you cannot change 1/2/3 during processing, but you can change 4 > (sensitivity). OK, Rawshooter calls it Exposure Compensation, not > Sensitivity. But since you cannot change 1/2/3... > > Please slide that Exposure Compensation slider right or left and see what > happens to the histogram. You can even recover clipping, isn't that a > sensitivity change? OK, let's call it software sensitivity, as opposed to > the hardware sensitivity at ADC stage, but we can also call it push > processing... Push processing can change ISO, can't it? > I think push processing is a very good analogy. You can't strictly speaking change the ISO on a digital camera - the sensor has a fixed sensitivity. You can only do exposure compensation and/or *emulate* a different ISO. It's the same thing with push processing, isn't it? It doesn't *really* change the ISO of the film, but simulates the appearance of exposures on a higher ISO film?
Maybe digital sensors respond to push processing in a better way than most film, though... - Toralf -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net

