Nice review Justin. I had purchased this lens a while ago and had to return it three times due to none of them were able to focus correctly without micro adjustment. Once they were adjusted the images were beautiful and I was able to capture tack sharp images at f/1.4 on most of them. Though I had returned it seven months ago due to it would not work on bodies that does not have build in micro adjustment function, I had always missed it.Which begs the question, if the 50mm Art can be calibrated using the USB dock, why are Sigma shipping lenses from their factory that require calibration to work properly? The flippant answer would be, to sell their USB dock. But seriously, the cost in returns and adverse publicity regarding the AF of this lens must be painful for Sigma to bear.
Last week, I decided to purchase it again and this time with the USB DOCK. The copy I received still needed micro adjustment to work; however, after spending two nights of adjusting and testing all focusing ranges in the Sigma USB Dock software, I can now say that it is tack sharp without any micro adjustment ☺.
Now, the big elephant standing in the room is: "would I need to recalibrate the lens again if I put this calibrated lens on another Canon EOS body?" Luckily, I do have access to cameras and after testing my calibrated Sigma 50mm f/1.4 ART on a T5i, 7D Mark II, 5D Mark III and 1DX by multiple photographers, I can confidently say that no calibration or micro adjustment will be required once a copy of a 50mm f/1.4 Art is calibrated correctly with the Sigma USB Dock and will work on any Canon EOS bodies.
By the way, this lens will also works (auto focus with all 61 focus points) with both Kenko 1.4x and 2.0x Teleplus Pro 300 DGX teleconverters on a 5D Mark III (so as Tamron 150-600mm DI VC USD but not the Tamron 28-300mm PZD VC). Using 1.4x @ f/2 images looks like taken from a "soft focus" lens; however, when using the 2x @ f/2.8 it is sharp (that was unusual!). Both become sharper when closed down one stop.
Thanks again for reviewing this product and nice to see your beautiful work on your website and flickr. Heavy it may be, I still rather use this lens than any other 50mm f/1.4 (or f/1.2) out there by any other manufactures.
You calibrate the lens mounted to a camera body. If you have two camera bodies that require any lens to have different afma settings, that is no different with the 50 Art, I mean how could it be the same on every body?
My problem is that it misses back and front to the point where it's impossible to get focus on the same spot twice in a row, and therefore any value almost will give the same percentage of sharp shots...
I decided to sell mine yesterday, but it gives me some incredible shots once in a while when the AF actually gets it right, so I can't decide whether to sell it or take 30 shots of each picture to get it right.