Originally posted by BigMackCam Sigma 30/1.4 Art has beautiful rendering, in-lens focus motor and excellent build quality. The only negatives are that it's not weather resistant, and it's quite big and heavy for an APS-C prime... but, f/1.4
The biggest negative with that lens is the randomly poor AF performance that lens provides on bodies from different manufacturers. I looked at that lens pretty hard, both in EX DC and Art flavors, and Canon users were complaining about it not acting right inre: AF on their cameras just like Pentax people have been unhappy with it.
I think the AF issues have been fixed in the DC DN version that came after the Art for DSLR's.
I've long complained that there should be something like a 25mm f2.4 or so lens made mostly of plastic for both full frame and APS-C shooters. Basically the same design characteristics of the DA 35 f2.4 but in this next jump wider. It seems like every other camera system offers something like this currently, sometimes limited to APS-C only (Canon's 24mm f2.8 STM pancake prime for instance).
It seems like the best alternatives right now is either used glass from Sigma or Pentax, or else zooms from Pentax, Sigma, or Tamron. "Yay".