Some time ago I had the chance to buy a Sigma Art 1.4/40 in EF Mount for a very good price (650€ new) and so I could not resist to take it. I have the MC21 and it worked fine on my S1R. The AF is not stellar and works as usual only with AF-S, but at the end it's fine if you take a little bit care.
I never had the chance to use or test the Panasonic 1.4/50, but a lot of people are saying the Sigma 40mm is comparable in any terms.
The Sigma is a beast, weighs more than 1.3kg incl the MC21, needs 82mm filters and is really big. But the results I received up to now are really fantastic. The next test will be astrophotography for some constellations with guiding. The old Art 1.4/50 DG HSM is weak at the corners (but only for astrophotography, not for "normal" pictures), showing coma and astigmatism (fully open). I expect the 40mm will do much better.
Pictures from a ballet group on location, all with S1R and the 40mm at 1.4
I never had the chance to use or test the Panasonic 1.4/50, but a lot of people are saying the Sigma 40mm is comparable in any terms.
The Sigma is a beast, weighs more than 1.3kg incl the MC21, needs 82mm filters and is really big. But the results I received up to now are really fantastic. The next test will be astrophotography for some constellations with guiding. The old Art 1.4/50 DG HSM is weak at the corners (but only for astrophotography, not for "normal" pictures), showing coma and astigmatism (fully open). I expect the 40mm will do much better.
Pictures from a ballet group on location, all with S1R and the 40mm at 1.4
