[Soran]

I purchased a Sigma 8-16m around a month ago, and my initial few test shots when I first used it showed no issues. Today I took it out with me to shoot some landscapes, and after wondering why the shutter was not firing, I realised that there was no autofocus happening It works fine in MF mode and testing it at home in low light, the AF/MF switch appears to work as the focus assist lamp would work in AF mode and not MF. So, Have I got a SDM style HSM failure, or is there some obvious noob thing I am missing?

[G and T]

I had a Sigma EX 70-200 f2.8 HSM II that had the AF motor repaired 3 times so I sold it before it was out of warranty and bought a Tamron instead.
Glenn

[philbaum]

I purchased a Sigma 8-16m around a month ago, and my initial few test shots when I first used it showed no issues. Today I took it out with me to shoot some landscapes, and after wondering why the shutter was not firing, I realised that there was no autofocus happening It works fine in MF mode and testing it at home in low light, the AF/MF switch appears to work as the focus assist lamp would work in AF mode and not MF. So, Have I got a SDM style HSM failure, or is there some obvious noob thing I am missing?

Try AF at the 16 end of it, as well as the 8 end. I know on the Sig 10-20, it wouldn't focus at all well at the 10mm focal length, but would at >12mm.