Helios Helios-44m-4

Sitting beside me today is a Russian lens, a Helios 44M-4. Fabled for its swirly bokeh, many portrait photographers own one. (I'm not saying "want", since it's so easy and cheap to get, you might as well have one.) Some sources claim it's a copy of the Carl Zeiss Biotar. I'll leave that research and digging around to you. My copy is in pristine condition. It came with my first film camera, a hulking, blunt-force Zenit 12XP. It was my first manual lens when I shot with my Canon 1300D, and I remember the wave of joy after managing to get a portrait with that much-discussed swirling bokeh.

I find this lens pleasant to use. The knurled focus ring is big enough to be comfortable. The aperture has half-stops, which is nifty (between f2 and f2.8, all the way to f11). I do remember finding the lack of an A/M switch annoying, but that's something you can easily fix. Just get an adapter with a board that presses down the aperture pin. (Or mod it at your own risk.)

Look out for flare. This thing flares like a beast. Keep that in mind and bring a lens hood.

If you shoot this lens wide open, you'll most likely get reduced contrast and slight softness. Not that bad for those dreamy portraits. Stop down and the lens performs much better, with pretty good microcontrast.

Color

If this lens doesn't flare, you get slightly warm colors. Personally, they remind me of pastels. Stop down and they get a lot more saturated. Shoot it wide open for that slightly worn-out, gritty look.

Bokeh

The easiest way to achieve the fabled swirl is to have a background with trees. The light coming through leaves and branches revolves around the center of the image. You'll need some practice to get it more pronounced and visible.

This lens is a good example of why decent-performing lenses don't need to cost thousands, or hundreds, or several coffees. It's cheap, it's plentiful. Get one and don't look back. The specific rendering when wide open might just be your thing. If you put the lens to your ear, you can hear thousands of forum users chanting "SAMPLE VARIATION" and "USSR QUALITY CONTROL" in unison, so keep in mind your copy might be better, or not as good, as one you've seen online.