12-23-2014, 03:44 PM
50mp is only 100 / √36 * √50 = 117.85% more resolution. So of those numbers of that website are in any way meaningful (i doubt it..), that would mean a D820 with 50mp would be rated 1238 points, not a meaningful difference to that Sigma lens.
Now back to the real world. When one measures the lenses, one can see a difference already on a 24mp sensor (the Zeiss being a bit sharper in the center). The difference on 36mp might be a tad more pronounced, but whether one actually sees the difference, without measuring it, is another thing.
Shooting wide open, the difference in character should be more important than any difference in resolution, in my opinion.
As to manual focus, it is a bit difficult to judge focus with a standard focus screen (some people are much better at that than others). I changed my focus screen especially for that purpose (big aperture, manual focus).
Now back to the real world. When one measures the lenses, one can see a difference already on a 24mp sensor (the Zeiss being a bit sharper in the center). The difference on 36mp might be a tad more pronounced, but whether one actually sees the difference, without measuring it, is another thing.
Shooting wide open, the difference in character should be more important than any difference in resolution, in my opinion.
As to manual focus, it is a bit difficult to judge focus with a standard focus screen (some people are much better at that than others). I changed my focus screen especially for that purpose (big aperture, manual focus).