Sigma 35mm f1.4: Vignetting

However, if you want to sort of fix all these problems that we talked about-- that means the detail at close focusing, the vignetting, the longitudinal chromatic aberration-- all of these things pretty much go away at f/2.8.

vignetting or dark Corners this is normal for a fast wide angle lens but the dark Corners you'll get on full frame really are strong I mean here's a picture at f2.8 and the same picture with the aperture wide open at f1.4 those are some seriously murky Corners goodness knows what could be hiding…

Not to mention nice fast shutter speeds even in darker situations, which can also be useful for getting the light that you need for video work.