>>4363321>f5.6 exposes the same anywhere.Sure, but the total amount of light you gather at f/5.6 grows with sensor size. That's one of the reasons why f/5.6 looks cleaner with a bigger sensor at the same ISO shooting the same scene. But the scene itself isn't equivalent, it's a shallower DoF. So if you need the deeper focus, for example if you are of the Orson Welles persuasion, then you'll have to stop down and raise your ISO. To claim aperture shouldn't be considered when comparing sensors of different size can only be ignorant or dishonest, there's no third option. Can you imagine Citizen Kane with a fucking f/2 equivalent aperture? It would ruin the entire masterpiece it is.