I recently purchased a Sony 70-200 F4 and have been testing it on my A7 (the very first one). I noticed that there's a clicking sound and the display (both in the LCD and EVF) flickers whenever I change the aperture value. I'm guessing this is because of the aperture blades, but the thing that's been bothering me is that there's no clicking sound nor flickering display when I'm using my other lenses - the 24-105 and the 28-70 kit lens. Is this normal?
I also noticed that the AF is quite poor when shooting in low contrast or low light situations. Not too low though, like the soft light of the sky during golden hour. Anyone else experiencing this?