It doesn’t come easy, doing street photography with a 28mm lens, but I’m trying hard because I like the results when I get it right.
I actually want to make use of what is generally thought of as a lens fault: curvature of field, meaning that the plane of focus is not flat but curved. For instance, you focus the lens at something at 6m in the center and then objects at the edges are in focus when they’re much closer (or further away, but that’s rarer). And I want to use scale focussing, autofocus is just not quick enough for street photography, so that rules out the modern Sony FE 2/28 for this specific use case.
Now most older 28mm lenses suffer from this lens fault, to an extent that it’s difficult to find one without it. All my Minolta SR-mount 28mm lenses suffer from it in varying degrees, the latest MD 2/28 relatively little. While I have a lot of Minolta 28mm lenses, most of them won’t fit the bill; closest came the earlier MD 28mm versions like this one, but in the end I wasn’t happy.
My favorite 28mm lens is the Olympus OM G.Zuiko 3.5/28mm but for some strange reason I can’t seem to make it work on the streets.
Reading up on Pentax lenses I came across the SMC Pentax-M 3.5/28mm which might fit the bill, going by some reviews and I got this one.
It appeared to offer very decent image quality, showing the ability to form a sharp image over almost the whole frame, only the extreme corners never sharpen up; see test shots. And it has considerable curvature of field, just what I was after.
In the next picture you can see how this can work to your advantage. The people in the centre are further away than at the right and both are almost perfectly sharp. I do a lot of this kind of scenes where people are fairly close by at the edges.
Because I have an incurable curiosity at what lenses can do on my camera, I also got hold of its somewhat faster brother, the Pentax-M 2.8/28mm.
Test shots here. Sharpness at edges and corners isn’t as good as that of the 3.5/28, but curvature of field is less so it’s not fit for my intended purpose. It will do fine though as a landscape lens when stopped down to f/8.
And now it’s back to making pictures, hoping that the Pentax 3.5/28 will magically make me a better photographer!