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It's been mentioned a few times on other threads but I thought I'd ask the question.....
We're all familiar with ISO and for most of us the general rule is (for image quality) we like to keep the ISO down as much as we can till we're forced to increase it either because the lens we're using wont go wide enough aperture wise or we want to use shutter speeds too fast for the available light.
I was thinking about the recent DSLR models which allow very high ISO and perform pretty well - but what if you want to slow things down and require ISO performance in the other direction ?
If I want to capture a little movement with a slow shutter speed with wide aperture for shallow depth of focus on a bright day - I have to start using ND filters or if taking it to the extreme - welding glass.
Is it not possible to push the limits of 'low' ISO like they're doing with 'high' ISO and make the sensor less sensitive - rather than more sensitive to light ?
...perhaps it's a case a case of why bother when folk can add filters ?
We're all familiar with ISO and for most of us the general rule is (for image quality) we like to keep the ISO down as much as we can till we're forced to increase it either because the lens we're using wont go wide enough aperture wise or we want to use shutter speeds too fast for the available light.
I was thinking about the recent DSLR models which allow very high ISO and perform pretty well - but what if you want to slow things down and require ISO performance in the other direction ?
If I want to capture a little movement with a slow shutter speed with wide aperture for shallow depth of focus on a bright day - I have to start using ND filters or if taking it to the extreme - welding glass.
Is it not possible to push the limits of 'low' ISO like they're doing with 'high' ISO and make the sensor less sensitive - rather than more sensitive to light ?
...perhaps it's a case a case of why bother when folk can add filters ?
, as I understand it the light and sensor in a digital camera are similar to sound and an amplifier in a stereo system. We know that very high ISO values act like an amplifier which is turned up to boost a weak signal (i.e. low light), but with very low ISOs the situation is more like a very loud sound being turned down in volume by the process of attenuation. In the case of audio, this smooths out some of the curves and makes the sound less dynamic, but in the case of bright light I guess that there would be a problem with stray light bouncing around in the camera and spilling over into adjacent photosites, if they are left to fill up very slowly with strong light at 'reduced amplification' (i.e. the attenuated levels which an 'ISO 25' would require) :shrug:.