I love gear. I don't need much in my photography, but I looooove playing with new lenses, cameras, film stocks, etc. the thing is, I am a student without a job, so I don't have loads of extra cash to spend on uneccesary equipment like some people. Thrift stores, Craigslist, and eBay are my main source of new toys. Lenses for full frame dslr's are rare at low price points, so I was impressed when I saw the Quantaray 28mm 2.8 for $25 on eBay. On paper, this has the potential to be a great budget lens. It's fast, it's small, and most importantly, it's cheap as hell.
When I got it in the mail, I was even more impressed. It feels incredibly solid, and I suspect it could easily survive a few falls. In fact, it was so heavy for such a small lens that, combined with a durable tube sock, it could probably be used as a makeshift weapon. In my opinion it feels just as sturdy as many manual Nikkor lenses. Everything including the focus and aperture rings are securely locked in, and as far as the exterior components go it is a dream to use. I was also pleasantly surprised by the half-stop aperture ring, which is especially useful when shooting film on cameras where shutter speed is measured in full stops. My only complaint is that the focus ring runs the opposite direction as manual Nikkor lenses, which takes a little getting used to.
Up until I started shooting with it, I liked everything about this lens. Unfortunately, the optics are absolute GARBAGE. While it performs reasonably well at close distances in the center of the frame, it is absolutely horrendous in almost any other situation. When focused to infinity the images are very soft across the frame, and even at moderate distances with it focused on an object, there are no parts of the image that I would consider "sharp". If you do choose to use this lens however, it is sharpest at f/8, with "reasonable" sharpness to f/5.6 and f/11 respectively. anything beyond is entirely soft, even at close distances. The worst part, however, is the corner sharpness. Unlike some lenses, the Quantaray is not only soft in the corners, but when "focused" in a way where the corners should be sharp, any highlights transform into short streaks similar to the way stars trail at long shutter speeds at night. If you are going to try this lens, it is only really good for close up shots, which, in my opinion, defeats the purpose of buying a 28mm lens in the first place.
The bokeh is actually pretty descent though. While its not "smooth" by any means, highlights are rendered nicely, and bokeh balls are nice and round. In fact if you like that bokeh ball look, this lens actually preforms above average, however you will find it very difficult to get a smooth out of focus background.
I didn't expect much from this lens, but it was even worse than I imagined. Kind of a shame too, because this is exactly the kind of tiny fast prime that I could see myself carrying in day-to-day situations. Unfortunately though, the low optical quality is just irredeemable.