04-09-2020, 12:25 PM
(04-09-2020, 08:58 AM)Brightcolours Wrote:(04-09-2020, 08:00 AM)Rover Wrote: The very old Sigma lenses are a bit of a gray zone... For example, I have the Sigma 14mm f/2.8 EX HSM lens that is not labelled DG - I believe there was never a DG version of that, it was just discontinued - which has worked fine on every Canon camera it's been paired with (40D, 1D Mark II N, 1D Mark III, 1D Mark IV, 1D X, 450D, 650D, 5D Mark II, 5D Mark III etc.) This model is from 1997/8 and has been discontinued in the mid-00s, so Sigma HSM lenses of similar vintage (denoted by the "crinkle" finish, or whatever it's called) are probably fine. Not so sure about the lenses from the "Zen" finish series that preceded it though.
A 1997 Sigma lens won't work (when operating the aperture). Just before the "DG" nomination, Sigma did exchange the electronics in their line up to make them compatible with the cameras that followed after the EOS D30 and D60. So your lens either was produced later than the 90's, or it had the electronics changed under the repair program Sigma used to offer for a few years.
DG (Digital Generation of lenses) did not stand for "compatible electronics" by the way... It designated improved back element coatings that minimised the strong purple fringing phenomenon that plagued early digital photography. The later introduced APS-C lenses sported the DC tag, C meaning crop (APS-C), which messed up the DG meaning a bit... DG now stands for "135 format full frame" basically.
Since you can not be sure if a non-DG FF Sigma lens is from before the electronics change or without electronics repair in the early 2000's, you best avoid them unless you can try them out before you buy (you take a photo with a closed down aperture setting, if no lens error occurs you are fine).
I know what the DG designation meant. My lens works regardless, and I've seen/heard of a few more specimens in the hands of other people, all work well.
I checked the Sigma UK history page and my lens is actually a 1998 model. It was one of the first EX designated Sigma lenses, and the (joint) third to get HSM focusing.
The 1997 models (300/4, 400/5.6) were the last of the ones that required hardware updates, AFAIR. Some are still sold second hand but of course getting one would be a risky endeavor. So I guess the 1998 introduction date really is the cutoff.