Sony pancake 16-50mm vignettes at 16mm.

of course correction if Off. RAW is not corrected.

if you shoot RAW+jpg, you'll see the jpg do not have vigneting because it's crop.

So, some would say this is cheating: this lense cannot make good 16mm pictures... but some reviewers on the net noticed something: the field of vew of the corrected image is equivalent of the field of view of the 16mm prime panacke sony lense. So, they conclude the uncorrected raw is in fact wider than 16mm, maybe 14mm or 15mm...

so seems the 16-50 is in fact opticaly something wider.

it's maybe a 14-50, but that have a very bad quality at 14mm... uncorreced. Once corrected, this make a average (but certainly not bad) 16mm picture!

but this have to be confirmed... another reviewer could't get the same result (uncorrected raw wider than 16mm)