Opteka 85 mm f/ 1.8 Aspherical Lens

Sharpness wide open

Sharpness stopped down

Size/form factor

Metal mount and filter thread

Price - and the advantage is a huge one

Weaknesses:

Somewhat stiff focus ring (had to lube it in the repair shop)

Not standard F stop indicators

All F stop and focus distance marks peeled off within months

Comments:

A suprisingly good performer, especially for the 60eur price (new). I've chosen the Lightdow version. I can easily compare it with Canon EF85/1.8 and I dare to say, that Lightdow performs better wideo open - a bit sharper with better CA control. The comfort of use is low - stiff focus ring, no F stop markings and bizzare stops. But It is small and light. 

First and foremost, image quality on my copy was very good. It's quite sharp and contrasty, and color rendition is pretty good. I pixel-peeped the test images I shot, and there is essentially zero color fringing (green or purple), which is an improvement over the much more expensive Canon 85mm f/1.8 USM.

Overall exterior build quality is quite nice, with metal lens barrel and 100% metal mount and metal aperture ring. It feels a lot more like a lens from the 1970s than one made recently, weighing in at 380g (~13oz). Focus ring has a nice feel to it, and is some kind of rubber with ribbing for grip. I was not as happy with the focus ring or aperture ring performance, however, as I was with their look and feel (see below).

Weaknesses:

On my copy, the focus rings gets very stiff as it approaches minimum focusing distance in the last inch or so of travel. I assume this is bad QC on Opteka's part (or whoever actually manufactured it). It's sticky enough that is distracting and makes it hard, in some cases, to get focus dead-on.

Also on my copy, the aperture ring is *very* hard to turn. And I don't care for the aperture presets they've chosen: 1.8 > 2.5 > 3 > 3.8 > 4.5 > 6 > 10 > 22.  There are more than two full stops between f/10 and f/22, and this lens doesn't allow any "in between" settings.

Comments:

Despite the QC issues with my copy of this lens, I think the Opteka 85mm f/1.8 is a great value. Image quality is excellent, and it's built like a tank. You can't really do any better at the $100 price point for a short telephoto lens. While it's not quick to focus or fast in terms of dialing in exposure, it is a great choice for still life and head/shoulder portraiture.

Text was taken from my longer review on this lens.