A fast affordable 50mm with silky smooth focus...
50/1.4 Pentax Super Takumar
Pentax has alway made wonderful lenses. There was a major chapter in my professional life when I was heavily invested in Pentax film cameras (the wonderful LX) and lenses. When it comes to classic Pentax glass, well, lets just say I am a big fan.
There are a number of different categories of Pentax lenses (more on this later) but one category, the old M42 screw-mount series of lenses, really deserves fresh consideration. Be warned though: the word is out and these lenses are "hot" items in the used lens arena.
Both still and video shooters are looking for "alternative lenses" these days. Pentax lenses like the old Super Takumars are a popular choice. There are many samples out there in the wild. They can be found quite cheaply, and they are very easy to adapt to modern DLSR cameras. In fact all you need is a simple M42 to EOS adapter to make them work on modern Canon camera bodies. These adapters are cheap, plentiful and can be easily found on-line on eBay and other outfits.
Buying a Canon EF 50/1.4 lens is an expensive proposition. I purchased a Pentax 50/1.4 Super Takumar for $50 at a used camera store. You will often find these lenses at garage sales etc for next to nothing. They usually come with an old screw-mount Pentax film camera. The camera might not be worth much but certain Super Takumars, SMC, M series, and A series lenses are most definitely worth a second look
My 50/1.4 Super Takumar includes a manual-auto aperture lever which comes ion handy. You have to sue stopped down metering with these kind of lenses. But this lever lets you focus with the lens wide open which gives you that f/1.4 brightness and then you can flip the lever over to manual for metering and actual picture taking at the aperture of your choice. Not all "alternative lenses" have this feature.
What else is there to like about these old Super Takumars? Well, you will notice how incredibly silky smooth the focus action is. Its like butter. Modern lenses do not feel this smooth while focussing.
How about image quality? I find my Super Takumar has a dual character: the image quality is quite soft wide open. But the softness is wonderful in a dreamy way that soft filters just can't deliver. Some fashion photographers regard these lenses as their "secret weapon" and models in the know will ask for these lenses specifically. Stopped down a bit these Super Taks get nice and sharp - the other side of their dual character.