Sigma 20mm 1.4 ART vs canon 16-35 2.8 III

Apart from the 1.4 factor, do you think the newest Canon comes close to resolution and clarity?

Most tests i've seen seem to indicate they are pretty close.
for example photozone.de

Sigma Art 20mm , tested at 50mp

Canon 16-35mm 2.8 III, @20mm tested at 50mm

Similar to this seem to be the result in other test sites, such as lenstip.com

Sigma 20mm art, tested with 5d3

Canon 16-35 2.8 III, center, tested with 5d3

Canon 16-35 2.8 III, FF edge, tested with 5d3

Does anyone has any personal experience or insigh with this dillema?

I dont care at this point for the zoom vs speed (1.4/2.8) debate. Just for the optics and IQ comparison of these two lenses.
Thank you in advance

The whole point is exactly the 1.4 factor and that is why you have no responses....

you either need the prime or you need the zoom. Not sure anybody would decide between the two on optics alone...

if you don't care about aperture, go for the lighter, cheaper 16-35LIS.

silly comparison.  silly that anyone cares about charts these days when all of the best lenses are "perfect"

ed rader wrote:

silly comparison. silly that anyone cares about charts these days when all of the best lenses are "perfect"

That is why i ask, you think that all these new lenses are already so good that they've reached a plataeu, and IQ differences are miniscule?

Sittatunga wrote:

Deorum wrote:

ed rader wrote:

silly comparison. silly that anyone cares about charts these days when all of the best lenses are "perfect"

That is why i ask, you think that all these new lenses are already so good that they've reached a plataeu, and IQ differences are miniscule?

There are a whole lot of other factors that affect IQ. That's why sites such as lenstip and photozone use so much space to talk about distortion, bokeh quality, coma, astigmatism, flare etc. There's also colour rendering, contrast and microcontrast which don't get talked about so much as they're harder to measure or illustrate consistently.

These are my thoughts and i wanted to hear other people's thoughts.
 I cannot believe that the best quality-prime, will produce the same image with the best quality zoom. 
 Yes, that is for shooting daylight landscapes, lets say @ f5.6-f8.

These tests seem to indicate that the lenses are more or less the same, smth that seems counterintuitive to me.

ffabrici wrote:

I have the 20mm ART and I have tried the 16-35L II.

Both er super sharp in the center even wide open and their edge and extreme corner sharpnes are comparable for the same apertures. Doownsides are found when used at large apertures: Coma for the ART and vigneting for the zoom.

Both are highly recommendable so thendesition is more dependent on your needs and wants than their performance.

I do also have the 16-35L IS, but others would prefer the 2.8 zoom. I find primes more challenging and rewarding to use but zooms are way more versatile for events and reportage photo shoots.

you mean you have tried the 16-35L III (mark 3)

?

ffabrici wrote:

Correct; the 16-35L III.

So more or less you agree with the first posts, IQ differences are miniscule. It all comes down to whether you need the speed of f1.4 or the versatility of the zoom. 
Thanks

Deorum wrote:

Sittatunga wrote:

Deorum wrote:

ed rader wrote:

silly comparison. silly that anyone cares about charts these days when all of the best lenses are "perfect"

That is why i ask, you think that all these new lenses are already so good that they've reached a plataeu, and IQ differences are miniscule?

There are a whole lot of other factors that affect IQ. That's why sites such as lenstip and photozone use so much space to talk about distortion, bokeh quality, coma, astigmatism, flare etc. There's also colour rendering, contrast and microcontrast which don't get talked about so much as they're harder to measure or illustrate consistently.

These are my thoughts and i wanted to hear other people's thoughts.
I cannot believe that the best quality-prime, will produce the same image with the best quality zoom.
Yes, that is for shooting daylight landscapes, lets say @ f5.6-f8.

These tests seem to indicate that the lenses are more or less the same, smth that seems counterintuitive to me.

Look, the reality these days is that the top zoom lenses are exceedingly good, approaching, and in some instances, surpassing prime lenses (e.g. 24-70LII vs 24/2.8IS). You are not going to appreciable differences in resolving power at f/5.6 and beyond.

the lenses I have now ar "PERFECT"