nburwell wrote in post #16045469
This is really good to know. It makes me re-think purchasing one on eBay, and just buying it from B&H where I wouldn't have an issue with returning it and getting another one. Although I would get a bit frustrated if the second copy I received was a dud as well.
I appreciate you bringing the quality control up in your post.
-Nick
Here's how I came to view the Samyang/Rokinon 14mm through my month-long journey to get a good one: it's so cheap because the manufacturer essentially throws you-know-what at the wall (i.e., customers) and sees what sticks. I wouldn't be surprised, based on my experience and reading reviews, if more than half of all copies floating around are noticeably inferior to what a "good" copy looks like. But, as you already mentioned, going through a reputable retailer with a good return policy allows you to get around this issue. It just might take some frustration and time if you're unlucky. B&H might be best, as even Amazon started to balk during my second return.
What you should be looking out for is de-centering. Both my bad copies were soft on the right side to varying degrees, especially when focused at or near infinity. Oh, and by the way, the focus markings are also often rather inaccurate (even on my final copy). Using live view and/or just doing some tests when you first get it make this less of an issue.