It's one of those old cheapies you can find everywhere on the internet, the Super-Multi-Coated Takumar 55mm/F1.8. It once was the standard lens on the legendary Pentax Spotmatic, the first 35mm camera with TTL metering. Revolutionary!
These lenses go for about 25 euro's (about 35-40 USD), but the performance of this little baby goes far beyond that price! They can be mounted on a modern Pentax dSLR through an adapter, and the same holds for at least Canon cameras. This combo gives you a very cheap classic short tele-solution perfectly well suited for portraits. But the lens can do much more! With some fellow Pentax enthusiasts, we decided to shoot one week with the different variants of this lens, and share the photos in a Dutch Pentax forum.
Rather than posting a technical pixel-peepers test of the performance of the S-M-C Tak 55/1.8, I will post some real-life examples of what this beauty can do. For more examples of better quality you'd better visit the mentioned thread at Pentaxian.nl!