« on: December 11, 2013, 04:24:05 PM »
qwerty, all I can say is that if the out of focus light wasn't reaching the sensor, then a f/1.2 image would like the same as a f/2 or higher image. I can tell you that is not the case at all - the f/1.2 image will have much shallower DOF. The effective ISO is getting an artificial boost, so we're being "robbed" of image quality in terms of noise, color, and DR (at least at higher ISOs). At the end of the day, fast lenses are still great for shallow DOF, fast AF, and they will always let in more light, even if the ISOs are getting a boost.