Why few Sigma and Tamron Reviews?
People are always asking me when I’m going to look at this or that from Sigma or fromTamron (Tokina is usually OK).
I rarely look at these junk brands because while their optics often are OK today, their mechanics are usually second-rate, and even if they work today, they are poor investments since 10 years from now it’s not that likely that they’ll work on the newest cameras.
The only reason people look down to Sigma and Tamron is to save money, not for quality. Personally, when money matters, I always buy used Nikon, Canon or LEICA lenses instead of new junk.
These junk brands are fading as most people make better decisions and buy online. Those brands were popular in the days of the old “retail” stores, because retail dealers pushed people into the junk brands because the stores made much higher profits. Junk brands give much higher profit margins to the store (much lower costs) than good brands. It was a perfect scam: the customer thought the salesman was being his buddy selling him a lens for much less money and often claimed to be made by the same company that makes lenses for Nikon or Canon (a common lie at retail), while in fact, dealers make more dollars on a junk brand sale because the profit margin is much larger on junk brands. A store might get a few percent profit on a name-brand lens (it’s not much), and might make 20% on a junk brand. You do the math.
So, since you asked, I ignore Tamron and Sigma, and strongly suggest used Nikon, Canon and LEICA lenses instead if you want quality at low cost. For instance, the Nikon 35-70mm f/2.8D is a superb genuinely professional lens, and sells for only about $400if you know How to Win at eBay. I’d much rather shoot with the pro Nikon lens than some Tamron or Sigma 24-70/2.8 blah blah blah.
The junk brands are all about additional dealer profit, not photography. The people pushing them know that people new to photography lack the experience to know what really matters in a lens, so they whip up something with nice specs like “24-70/2.8 VC III XR 123 XYZ” or whatever, but fail to deliver on the guts inside that you can’t see.
When I have used junk brands, their mechanical quality does not impress, and most of the time when older junk brand lenses come into my ranch, they no longer work with current cameras. Old Nikon, LEICA and Canon lenses always work well when I get them.