They claim best sharpness for f/5.6 ... that is 5 (plus a bit) f-stops
down from max-aperture ... which is at least unusual for a prime.
Most of them get their best values 2 to 3 stops down.
Looking at the MTF-curves ... while things look ok-ish at f/5.6 ...
sharpness is next to nonexistant at f/0.85 ... well, probably
sharpness is not the reason why one would buy such a lens.
I do find some of the sample images nice ... but at the price they ask
for it, I easily get a used 5D plus a 50L which allows the same
type of images (with the plus of AF and aperture controlled by the
camera). So, likely this 40/0.85 will remain a gimmick for those who
already have everything else.
Just my thoughts ... Rainer
down from max-aperture ... which is at least unusual for a prime.
Most of them get their best values 2 to 3 stops down.
Looking at the MTF-curves ... while things look ok-ish at f/5.6 ...
sharpness is next to nonexistant at f/0.85 ... well, probably
sharpness is not the reason why one would buy such a lens.
I do find some of the sample images nice ... but at the price they ask
for it, I easily get a used 5D plus a 50L which allows the same
type of images (with the plus of AF and aperture controlled by the
camera). So, likely this 40/0.85 will remain a gimmick for those who
already have everything else.
Just my thoughts ... Rainer