I used the Olympus 17 mm at wide open aperture of f/1.8 to take these. The primary reason I occasionally use prime lenses is because of the wider apertures. Wider apertures give me more flexibility to continue photographing in low light and give me a shorter DoF so that I can blur out, or soften, the background like in the above images.
I am also getting a 45 mm prime lens to use for these types of images. My plan is to also use it occasionally for my railroader’s project when I need to isolate a small detail as well as for some building details in town.
In the past when many of my kit zoom lenses that came with cameras were so poor, I started photographing with prime lenses to gain image quality and lighter-weight systems. I am now finding that with the new zoom lenses, especially with Olympus micro 4/3 sensor, this isn’t as necessary and that I am using the zoom lenses more and more for the flexibility in compositions. When I started my project of the railroaders I assumed that I would need to use prime lenses to have sufficient image quality and fast-enough shutter speeds inside in poorer light, but I am happy to find that isn’t always true with my Olympus E-PL5 and the 14 – 42 mm lens.