Originally Posted by Freakscene
Did you switch to zooms for optical quality or flexibility reasons Chris? I'm interested. I need a hiking camera.
Flexibility mostly. My work is mostly social documentary and architecture. For architecture it is hard to 'zoom with your feet' because the place you stand determines relationships between different objects at different distances in the photo. With a prime, the place I'd have to shoot from to get the composition I wanted often threw off subject relationships. Zooms let me stand where I need to be then zoom to get the angle of view I want.
Olympus's Pro f2.8 zooms are INCREDIBLE. They're sharper than the Canon L zooms I used before and fully equal to all but the very best prime lenses.
The Olympus 45mm f1.8 lens is about equal in sharpness to the 12-40mm f2.8 zoomed out to 40mm, but the Olympus 45mm f1.2 Pro lens is sharper than the zoom. BUT that 45mm f1.2 is a $1200 lens. It costs more than the 12-40mm Pro zoom. The 45mm f1.8 is delightfully cheap, and tiny. I have one I use for portraits because the bokeh is slightly nicer then the 12-40 zoom. I'd love the f1.2 lens but can't afford it; I wouldn't use it enough to justify the cost.
Olympus has one prime that is awful; the 17mm f1.8. It is the worst modern lens I have ever used from any manufacturer. Very sharp in the center, even wide open, but becomes very soft even a small distance from the center. I tried and returned 5 of them and all were identical; its just a poor design. 2/3 of the way out from the center and it looks like a holga, absolutely ZERO fine detail resolution, which is worthless for architecture work. The 12-40 Pro and 7-14 Pro zooms are both incredibly sharp at 17mm all the way to the corners.
If you want tiny primes, then the aforementioned Olympus 45mm f1.8 is wonderful. So is the Olympus 25mm f1.8; I sold mine and kind of regret it. I might buy a new one soon. The 17 sucks, so I had the Panasonic Leica-branded 15mm f1.7 and it was wonderful too. I sold it because as good as it was, it was no better than the Olympus zooms I had, and it sat unused for months. Its a $500 lens, I freed up the money for something else I needed. But if you want to stick to a set of small primes, it is a very good lens.
Interestingly, the small primes are almost too tiny for the OM-D E-M1 mark II; that camera balances better with the big pro zooms.