I have been cataloguing the balance of my 2016 photos over the last week, which I have to admit is most of them. I'm sure others are far more organised and diligent than me. Last year I started to use higher ISOs than previously in situations where I needed fast shutter speeds with long lenses in poor light. What I have noticed in my cull is that at the same ISO setting on the same camera, some images have much more noise than others. My initial thought is that the better images are those with a good spread across the histogram, but are there other factors to consider? I am using a Canon 7Dii and always shoot in raw. In most cases the noise can be reduced to manageable levels levels in processing, but it would be good to know how to reduce noise in camera.