The Sigma 30mm f/1.4 DC HSM is a new standard prime for digital SLR cameras with APS-C sized sensors. With an optical formula comprising nine elements in eight groups and an iris diaphragm with nine rounded blades (and no “EX” designation in the name), this lens features a completely different design to the older Sigma 30mm f/1.4 EX DC HSM, which was introduced back in 2005. It also has a shorter close-focusing distance of 30cm and a higher maximum reproduction ratio of 1:6.8. The filter attachment size is unchanged at 62mm, as is the 30mm focal length that translates into 45mm on Nikon and newer Sigma bodies, 48mm on Canon and 51mm on older Sigma digital SLRs. As part of the manufacturer’s ‘Art’ line, the new 30mm f/1.4 DC HSM is compatible with Sigma’s separately sold USB dock accessory and Sigma Optimisation Pro software.