You apparently do not fully grasp what an ISO invariant sensor allows one to do. It is not just a matter of getting the exposure correct; it is the ability to deliberately under exposed by pne, two, three, or four or five EV in order to build shutter speed if needed in dim lighting and to then brighten the exposure in software, later. Please look at the above example photographs of what a Canon 5D series full frame can do; it is so far behind what a Nikon D600 or D610 can do for 2,000 fewer dollars. I cannot help you understand why a market leader would not improve its products when it's competition has improved so tremendously. Two of us have told you that Canon neglected to improve its sensor technology level for over a decade, because they were in a market leading position and there was no incentive to markedly improve their sensor technology levels. Nikon went outside of its own company to procure the best sensors possible. Canon stuck with its own, home-grown and inferior sensor technology. This is about technology and at times, market leaders do not have the best technology--but they DO have a sales leadership position.
