My reviews are typically more user experiential based and certainly based on my own experience, prejudices and feelings more than anything else. I do try to throw in at least the most basic of “formal” testing, basically just shooting a giant wall map I have at a range of apertures with the camera sitting on a tripod and focus locked for all of them.
That out-of-the-way I ended up getting an Olympus m.Zuiko 17mm f/2.8 lens back in late June. I had felt like there was a big gaping hole between my Panasonic 14mm and Sigma 30mm and I wasn’t able to find a Panasonic 20mm like I had wanted (at least at a reasonable price) before a big family reunion. After reading many reviews maligning the lens and a number of user reviews praising it, I figured that if i could find it for cheap used, why not. The worst that would happen is I would hate it and turn around and sell it losing only a few dollars in the transaction. I managed to acquire the lens for $130 in like new condition with lens caps.
I was prepared to dislike the lens, but the opposite is very much true. The lens has a certain character to it that I like a lot. It is by no means a perfect lens. Resolution is at best mediocre, though at least as good as the 14-42mm II Olympus kit lens. However, micro contrast is good on the lens and frankly I just love the size, handling, color reproduction, bokeh (when close enough to produce any) and focal length so much.
Speaking of size, the lens is 22mm thick, 57mm in diameter, weighs 71g, takes 37mm filters has 5 aperature blades (rounded), is composed of 6 elements in 4 groups (1 aspherical) and has a minimum focusing distance of .2m (1:9 magnification).
A couple of other negatives to note about the lens is it tends to produce a fair amount of chromatic aberration, but it isn’t terribly complex and is easy to remove in lightroom. In addition, it uses a traditional focusing motor, not an MSC motor like most of Olympus other lenses. So the lens does produce some noise focusing, but it isn’t terribly objectionable (it is loud enough to pickup during movie recording, but won’t over power anything except very quiet scenes). Focusing speed is also slower than most m4/3 lenses. On an E-PL1 it takes around .8-1s to focus if focus locks right away. If it hunts before finding focus it can take a good 2s to hit focus. On the OM-D E-M5 it takes around .5s to lock focus if it hits it right away, with hunting it might take a little over a second to lock focus.
For positives as I mentioned the micro contrast is pretty darned good on the lens, the Bokeh is nice and smooth, the price is extremely low, especially for a used or refurbished lens and the small size and weight aren’t going to be real back killers.
Click on the images to view 100% crops from the map resolution test. Center on the left, extreme top right corner on the right. The images were taken with apertures (descending order) f/2.8, f/3.2, f/4, f/5.6 and f/8. As you can see the center is generally pretty good across the range but seems to clean up/sharpen up just a tiny bit around f/5.6 through f/8. In the corner things are softer, but they improve slightly on stopping down to even just f/3.2, further at f/4 and are probably the best at around f/5.6. You can also see that vignetting slowly disappears and is mostly gone at f/4, but takes till around f/5.6 to be completely gone.
Below are a pair of sample images converted from RAW with minimal/no sharpening or noise reduction applied. The storm picture had the shadows of the foreground dropped some, but otherwise untouched. Click the images for 100% JPEGs.
F/3.2, 2s, ISO400 f/2.8, 1/1000s, ISO200