Review on Sigma 18-35mm F1.8 Art DC HSM Lens - Canon Compatible, Black (210101) by Keisuke F Kuga ᠌

This zoom, it seems to me, is a revolution in lens construction. We were taught that there is no lighter than 2.8 zooms; it turned out that the lenses also have "firmware". Sigma did a great job. A very high-quality thing, noticeably heavier and 24-105 and 70-200 LIS with relatively small sizes (how much glass did they stuff into it?). According to the picture, no compromises, starting from 1.8. Sharp, little distortion, aberrations. Aperture 1.8 allows you to do on the "crop" what no zooms previously allowed. The color rendition is slightly warmer compared to the "native" optics, but it is so "slightly" that it is not clear: is it "Sigma" yellow or "Canon" blue? Autofocus is quiet, but somehow strangely tapping. Autofocus is the same fly in the ointment in the Sigma barrel of honey. I didn’t think that at a wide angle, where sharply “from the belly” to “infinity”, there may be problems with focus, but with such aperture, the depth of field is centimeters, and when the aperture is covered, the meaning in this lens disappears. Sigma autofocus does not provide accuracy in phase focusing, and it's not about front-back focus, which is solved by correction in the camera, or even better, using the Sigma docking station (another technological breakthrough). A camera mounted on a tripod can focus differently each time and I'm not sure that I got a sharp picture even in the 7D viewfinder. On my copy there were not the slightest scratches on the bayonet contacts. They don't even try to align lenses at the factory? Nevertheless, I decided not to take the lens back to the store. Firstly, the Samyangs, Zeiss, and the new Sigma with the Zeiss are trying to compare, there is no autofocus by definition; secondly, when using Live View, the focus hit is 100 percent. I have 7D, and the owners of 70D will be even better. Thirdly, I hope that with the release of new firmware, Sigma will be able to improve phase autofocus. And most importantly, no other manufacturer has such optics.