See my initial comments on disappointing performance of the Sigma 35mm f/1.2 DG DN Art.
One of my first steps with the Sony A7R IV testing is to pick out the wheat from the chaff, in terms of lenses—I have no desired to head to Yosemite and shoot with a lens that has an issue. Thus this test with two samples of the Sigma 35mm f/1.2 DG DN Art—I was lucky in getting one sample a month ago, and deferring testing it until I got another, because the first sample looked “off” even on the "only" 42 megapixel Sony A7R III.
I shot this series with two samples of the Sigma 35mm f/1.2 DG DN Art, my experience over the years suggesting to me the first sample was “off”, a bad sample. This comparison proved me right, and is thus excellent for anyone looking to see how sample variation can change the impression of a lens significantly.
While the same core behaviors are present, irrespective of focus the 2nd sample is distinctly superior through at least f/4. That’s a big deal for an f/1.2 lens, since the wider apertures are presumably the reason one buys it. Given what I’ve heard from two other users, there may be many not so great samples out there*.
Includes images up to full camera resolution for the good sample, and comparison crops for both samples showing the differences in performance.
The wood grain makes an excellent testing pattern for both lenses under controlled circumstances. It also shows off the resolving power of the Sony A7R IV sensor.
* High performance lens designs require tolerances that can be difficult to achieve in manufacture—there are many fine lens designs which are never built because it would be too hard (expensive) to reliably built to the designed performance level. Sigma’s quality control needs to be improved, and it raises the issue of whether an advanced design will retain its performance over time after minor bumps and such.