Actually, the linked comparison is actually unhelpful
if it is about portraits. The linked page is entirely about
blur in out of focus parts. And as such, it didnt,t even use
comparable lenses. A 50/1.8 against a 85/1.4.
With the same line of thought, one could have shown, that
using comraable settings leads to absolutely comparable results,
and therefore Crop-1.6 is as good as FF if it comes
toportraits.
On top of that ... comparing a studio portrait, where oof-blur
is next to unimportant, would have shown that crop-1.6 can
even be a slight advantage .... that is if you want the whole
face sharp.
Rainer
It's not about the background blur, but about the perspective and face appearance. I rarely use my 50mm at f1.4
Using lenses wide open is not a rule in portraits.
And here it is. Clear we can use both. However yes for the viewfinder shallow DOF full frame has a slight edge.
For me both are excellent concentrate on other important issues for portraits especially the lighting
It's 2016 and people still don't get it. It's the system which makes a difference.
A Fuji 56/1.2 would be on par with that Sony at f/1.8. A medium formar camera with a 80/2.8 lens would have a deeper DOF, which would be "worse" according to the author.
I swear one day I'll go home in a rage and I'll write an article about this.
This and "focal length affects portraits" myth.