NEX-6: Front Curtain Shutter?
Just leave it on unless it gives you trouble- it makes the shutter quieter and reduces the delay between you pressing the shutter and the exposure starting.
The down side is that with some wide-aperture and telephoto lenses you can run into exposure issues at very high shutter speeds. It doesn't affect any E-Mount native lenses, so it's nothing to worry about unless you're adapting A-Mount or third party.
|Fangorn Forest by cand1d|
|Yosemite Falls with Moonbow by Jonathan Shapiro|
from Best Landscape of the Week 4