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Categories: all aviation bicycle gadgets misc motorcycle theater Mon, 19 Jul 2010A quick recap of our story so far. Back in February, I took the plunge and bought myself a very nice lens, a Sigma 24-70mm f/2.8 HSM lens. It's roughly equivalent to the $1500 Canon lens of the same specs, but for $600 less. It was, at the time, the most I'd ever spent on a single piece of camera equipment; that includes the camera it was going on to. Fast forward a few months to June. I was talking with a friend, and we got to talking about autofocus, how it works, and how to test that it was working right. He recommended a test page, and I tried it out. Lo and behold, my new 24-70 lens was front-focusing a bit (the point that was actually in focus was about 10mm in front of where it should have been). So, I contacted Sigma, confirmed that they could fix the problem, and sent it in. A couple weeks later, it comes back. I excitedly fix the lens to the camera, and check it out. Nope, it's still out of focus. Oh wait, once I take out the camera's adjustment (which I'd put in before), it's way out of focus! It looks to my critical but unpracticed eye that they adjusted the focus point by 10mm alright, but in the wrong direction! Ok. Call Sigma back, explain the situation. They're very nice about the whole thing, offering to ship the lens back to them at their own expense. Get it shipped off, and the waiting starts. Almost two weeks after it was shipped off (having requested expedited service, since I'd already had the lens in once before), I got a phone call from them. It was one of their techs, and the (fairly confused) conversation boiled down to them saying, "Our calibration procedure doesn't cover the situation your test shows," and me asking, "So, the lens isn't guaranteed to focus in that situation?" The answer seemed to be that sure, it should, but that's not what we're testing for. (For the nerds in the house, I was testing at 70mm focal length, f/2.8, focused ~1.5 feet from the lens -- which is within its nominal capabilities.) There was a strong undertone of "Why would you do that? It's not a macro lens. You're an idiot, aren't you." Now, nearly two weeks after that phone call (the lens came back to me three weeks to the day after I sent it, so take all my "two weeks" descriptions with a grain of salt), it has arrived at my desk again. The note that came with it says:
IF YOU WANT THE BEST RESULT WE NEED YOUR CAMERA WITH THE LENS. CHECKED ALL IN GOOD WORKING ORDER. That sounds to me like they helpfully left the lens with its even-worse calibration in place. I'm not sure why my camera should be that different from their camera. I know that I saw the exact same error with two very different camera bodies (an XTi and a 7D), so it's hard to imagine that their test 7D could have been so vastly different. Perhaps the most galling thing about the whole experience was that phone call. The tech sounded like he was rolling his eyes and making the yapping-mouth gesture with his hand to the other guys in the room as he talked to me. It's news to me that a lens should be expected to not accurately focus within its design parameters. The fact that it has the problem doesn't make me feel very confident of its ability to accurately shoot the demanding photos I'm taking (low light, moving subjects, etc.). The fact that I had to send the lens back twice with a $900, top-of-their-line piece of equipment is very worrying, particularly if (as it appears) the second trip to the factory resulted in them leaving things exactly as they were after the first trip messed it up. The half-suppressed "You're a complete idiot" vibe is just icing on the cake. Of course, the real test will come tonight, when I can bring lens and camera together. I'll have an update soon with the outcome, but if at all possible, I'm never going to deal with Sigma's warranty service again. The method I've heard described for dealing with this is to buy 3 copies of the lens you want, then send back the two with the worst focus. An expensive way to do it, but it honestly sounds more surefire than going back to the factory for adjustments. Color me seriously unimpressed. Posted at 13:43 permanent link category: /misc Categories: all aviation gadgets misc motorcycle theater Written by Ian Johnston. Software is Blosxom. Questions? Please mail me at reaper at obairlann dot net. |