http://9to5mac.com/2015/09/28/iphone-6-diary-camera-test/
Jump to "Low-light Photos"
"
The 6s shot is noticeably less sharp due to the greater level of noise-reduction applied by the phone.
This reinforces what I’d long said: that Apple was right to refuse to enter the megapixel race and concentrate instead on quality rather than quantity. The more densely-packed sensor in the higher megapixel camera requires more aggressive noise-reduction to overcome the increased noise – and that is achieved at the expense of detail. So the higher resolution image does, in low-light conditions,
end up less detailed than the lower resolution version.
This is, unfortunately, what happens when people who know nothing about photography simply count pixels and criticize Apple for falling behind. The company refused to play that game for a long time, but I guess this is the point at which it feared it would be panned for remaining with an 8MP camera for a fifth generation (after the iPhone 4S, 5, 5S and 6).
At a pixel-peeping level, then, the iPhone 6s sensor is actually a retrograde step, sacrificing detail for pixel-count."
So, is iPhone 6s camera worse than 5s? In low light, I would say yes. It was bad decision to enter megapixel race.
