Title: Nice photos, but horrible build quality and failure prone
Review: Well, when it works, it takes nice shots. The large aperture makes for some pretty good bokeh for the price. However, most copies will not accurately focus throughout a range of distances (for example, mine was spot on until the subject got about 6 feet away, then it was extremely inaccurate from there to infinity). The autofocus mechanism is also failure prone and if it happens out of warranty (it WILL happen) it costs about half the value of the lens to have it fixed. You can sort of protect against the AF failure by storing the lens with the hood attached, but my copy failed while using this method. I'd go with the cheaper f/1.8, or the slightly more expensive Sigma 50mm f/1.4 if I had to do it again. Simply not worth the trouble and I've gone through three copies of this thing. All were not acceptable.
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