If I could only have one lens, and that one lens had to be a prime, then the 17mm f/1.8 would probably be the one lens I’d choose. Of course that’s a choice that no one actually has to make. But the field of view provided by this lens is a popular choice for one-camera-one-lens people, and is why the Fuji X100 and Sony RX1 series embrace this field of view. (17mm in Micro Four Thirds is conventionally considered equivalent to 34mm on a full-frame camera, but see my blog post on the Micro Four Thirds focal length multiplier.)
This lens is great for taking touristy photos of buildings in Manhattan, as seen above in a photo I took earlier today. A very cold day in New York, the temperature was in the low 20s.
Yesterday I wrote that the Olympus body cap lens is the only lens that makes a Pen-F camera pocketable. Even though the 17mm f/1.8 is the third-smallest Olympus lens (or fifth-smallest if you count the two body-cap lenses as lenses and not body caps), I say that the Pen-F is definitely not pocket-sized with this lens on it. Although technically I was able to stuff the Pen-F with 17mm lens into the large pocket of my winter coat, a trick that certainly would have been impossible with the much larger and heavier 12-40mm, it wasn’t a very elegant fit.
On internet forums, there seems to be some negative sentiment about the sharpness of this lens. I think this lens is pin sharp when stopped down. Wide open: I previously did a test against the 12-40mm and don’t see anything wrong with the wide-open performance. The 17mm lens is a little bit more sharp at f/2.8 than it is at f/1.8, but that’s hardly something to be shocked about. The lens still seems decently sharp even wide open.
So I don’t know if the negative sentiment about this lens comes from:
1. Unrealistic expectations. (I do agree that this lens is a bit overpriced.)
2. Bad quality control. Maybe some people have bad copies of the lens.
3. One particularly negative review that came out shortly after the lens was available for testing, even though their own tests showed this lens is as sharp wide open at f/1.8 as the Olympus 14-42mm kit lens at 14mm stopped down to f/5.6, and sharper wide open at f/1.8 than the kit lens ever gets at 28mm or 42mm at any f-stop.
I may add the warning that this lens has some noticeable field curvature, so if you take a picture of a brick wall at f/1.8, the corners will definitely come out soft.