Originally posted by ScooterMaxi Jim Frankly, a one-inch shift in close focusing on a 14mm lens (especially one that needs to stop down to f/4 to perform at its best) is barely perceptible. However, an f/8 shot with the same lens that cannot quite reach infinity is a real problem.
Being able to find infinity is also helpful. And at minimum distance shooting small objects, an inch makes a big difference in how big in the frame it will appear.
Quote: I wonder how many home engineers have gone straight ahead with recalibration just a day or two after getting the lens, and just happened to discover that their sloppy work resulted in a "manufacturing defect" allowing them to return the item.
An extreme minority, if any. Especially since it is so easy to try again and get it right -- you're just adjusting the infinity stop, if it is in the wrong place, you just move it again. Not much that can go wrong or be sloppy. If you mean try to adjust the decentering yourself, that would be an even smaller number, but presumably only made up of people that had done that sort of thing before. And even if they did return it, it deserved returning or they wouldn't have been trying to fix it in the first place. So I think this happened approximately zero times.
Quote: Perhaps some of them even tried this two or three times, taking greater care each time until they finally got what they wanted (a lens that focuses at infinity at f/2.8, but doesn't quite get there when stopped down). I suppose that could happen, and Samyang would get all the blame. Not that one person did this, but possibly some returns got shuffled back out the door of the retailer.
So this extreme minority (that I would reasonably estimate to be actually none) would also have to be returning to a dishonest retailer who re-sells defective returns that are supposed to be sent back to the manufacturer. That's a pretty tortured and unlikely scenario to account for the number of reports of these problems, or even a single report.
Quote: By the way, I'd be curious to know why anyone would feel like they should go all the way to a fourth copy rather than seek a refund for an inferior product. Possibly it isn't such a bad item to be going through so many hassles.
And I'm curious to know why someone would feel it was so important for them to be right that they seek to imply that other's experiences are not really happening. And who said it was a bad item? But the reason was of course I wanted a good copy. The reviews are all glowing about how sharp it is and how little CA, but they also warn that you must get a good copy because decentering is common. Plus what actually happened is that I bought the first one mainly because it was on sale with an incredible deal (<$200 at the time when they were selling for >$300), and I tested it, but not enough (the center was good), and then ended up not using it. (Really I wanted a good wide-angle that was full-frame capable for the future, but I also have the Sigma 8-16 so I tend to use that, and I was in the middle of a cross-country move about that time as well.) Anyway, I eventually got it out again, but past the return period when I discovered some of the edges weren't so great. So sent it back as a warranty exchange as my only option other than trying to adjust elements myself. (I couldn't sell it to someone else in good conscience.) Exchange copy was worse than the first one, sent it back again. And then while I was waiting for that, there was another good sale on it so I bought another one just to increase my odds. I really wanted a good one! And so then they both arrived and I had two to compare side-by-side -- both were much better than the first two, and so I kept the one and returned the other. And then lately I've been doing this close-up wide-angle stuff, and it is good for that...