How about this at 25600 ISO Reyces. No flash in a small concert venue. It was much darker than the way this photo looks. If you are looking for low light performance to focus as well as be able to get clean shots, the 6D will not let you down. Don't let people tell you that the outer focus points are bad, they work with the right amount of light, but the center focus point is almost perfect even in limited light.