Sony Nex-5N with LA-EA2 and 16-50mm f2.8 DT

Hi.

I bought the 16-50mm f2.8 lens to use with my Nex-5N and LA-EA2. I have noticed that there is vignetting in the corners at 16mm f2.8, which tells me that the Nex-5N firmware does not do auto correction for this lens and LA-EA2 combination; I leave mine turned to auto camera lens correction for all three. Can others confirm this finding?

Also, I notice that when the lens is not used at maximum aperture, that after I press the shutter button down that there is a slight lag while the aperture blades close down (first click) followed by the shot and the second click of the shutter. Have others experienced this as well? I'm finding that this loses the benefit of electronic first shutter of the camera.

BT