Lens reliability — Sigma vs other brands

If you’re considering Sigma lenses for your Nikon or Canon body, be sure to read the comments on reliability found at lensrentals.com. Read the entire page for details.

Since day 1 the Sigma brand has always been a bit of a money loser for us: they broke more frequently than the other brands. Our techs coined the phrase “Sigma’d” to describe any lens that didn’t function. When they did break, the repair turnaround time was, to be charitable, leisurely.
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Sigma lenses failed at a rate of 30% per year, compared to less than 5% for Canon, Tamron, Nikon, Tokina, and Zeiss. We weren’t losing a little bit of money anymore, we were losing a fair amount. More importantly, far more importantly, we had customers who rented lenses for important shoots and the lenses failed to work properly. Sigma was about 5% of our rentals but almost one-third of our customer complaints.

While I’ve had out-of-the-box optical issues with Canon and Nikon, I’ve had no outright failures (none) with 50 lenses or so. I have had some minor glitches with both Canon and Nikon, but that’s it. And I’m not sure how a Zeiss ZF lens could ever fail (excepting the lens hood).